diff --git a/app/src/main/java/org/andbootmgr/app/DroidBootFlow.kt b/app/src/main/java/org/andbootmgr/app/DroidBootFlow.kt
index c96761d6..12d6d80f 100644
--- a/app/src/main/java/org/andbootmgr/app/DroidBootFlow.kt
+++ b/app/src/main/java/org/andbootmgr/app/DroidBootFlow.kt
@@ -44,7 +44,7 @@ class DroidBootWizardPageFactory(private val vm: WizardActivityState) {
 			Input(vm)
 		}, WizardPage("shSel",
 			NavButton(vm.activity.getString(R.string.prev)) { it.navigate("input") },
-			NavButton(vm.activity.getString(R.string.next)) {}
+			NavButton("") {}
 		) {
 			SelectInstallSh(vm)
 		}, WizardPage("select",
@@ -150,7 +150,7 @@ fun SelectDroidBoot(vm: WizardActivityState) {
 						val json = JSONTokener(jsonText).nextValue() as JSONObject
 						val bl = json.getJSONObject("bootloader")
 						val url = bl.getString("url")
-						val sha = bl.getString("sha256")
+						val sha = if (bl.has("sha256")) bl.getString("sha256") else null
 						vm.flashes[flashType] = Pair(Uri.parse(url), sha)
 						nextButtonAvailable.value = true
 					} catch (e: Exception) {
@@ -181,7 +181,7 @@ fun SelectInstallSh(vm: WizardActivityState) {
 			vm.nextText.value = stringResource(id = R.string.next)
 			vm.onNext.value = { it.navigate(if (!vm.deviceInfo!!.isBooted(vm.logic)) "select" else "flash") }
 		} else {
-			Text(stringResource(R.string.choose_droidboot_online))
+			Text(stringResource(R.string.choose_install_s_online))
 			Button(onClick = {
 				vm.activity.chooseFile("*/*") {
 					vm.flashes[flashType] = Pair(it, null)
@@ -197,16 +197,16 @@ fun SelectInstallSh(vm: WizardActivityState) {
 						val jsonText =
 							URL("https://raw.githubusercontent.com/Android-Boot-Manager/ABM-json/master/devices/" + vm.codename + ".json").readText()
 						val json = JSONTokener(jsonText).nextValue() as JSONObject
-						val bl = json.getJSONObject("installScript")
-						val url = bl.getString("url")
-						val sha = bl.getString("sha256")
+						val i = json.getJSONObject("installScript")
+						val url = i.getString("url")
+						val sha = if (i.has("sha256")) i.getString("sha256") else null
 						vm.flashes[flashType] = Pair(Uri.parse(url), sha)
 						nextButtonAvailable.value = true
 					} catch (e: Exception) {
 						Handler(Looper.getMainLooper()).post {
 							Toast.makeText(ctx, R.string.dl_error, Toast.LENGTH_LONG).show()
 						}
-						Log.e("ABM droidboot json", Log.getStackTraceString(e))
+						Log.e("ABM install json", Log.getStackTraceString(e))
 					}
 				}.start()
 			}) {
@@ -345,6 +345,7 @@ private fun Flash(vm: WizardActivityState) {
 				"BOOTED=${vm.deviceInfo.isBooted(vm.logic)} SETUP=true " +
 						"${tmpFile.absolutePath} real"
 			).to(terminal).exec()
+			tmpFile.delete()
 		}
 		terminal.add(vm.activity.getString(R.string.term_success))
 		vm.logic.unmountBootset()
diff --git a/app/src/main/java/org/andbootmgr/app/FixDroidBootFlow.kt b/app/src/main/java/org/andbootmgr/app/FixDroidBootFlow.kt
index b6acae1d..50fb9785 100644
--- a/app/src/main/java/org/andbootmgr/app/FixDroidBootFlow.kt
+++ b/app/src/main/java/org/andbootmgr/app/FixDroidBootFlow.kt
@@ -77,6 +77,7 @@ private fun Flash(vm: WizardActivityState) {
 				"BOOTED=${vm.deviceInfo.isBooted(vm.logic)} SETUP=true " +
 						"${tmpFile.absolutePath} real"
 			).to(terminal).exec()
+			tmpFile.delete()
 		}
 		terminal.add(vm.activity.getString(R.string.term_success))
 		vm.activity.runOnUiThread {
diff --git a/app/src/main/java/org/andbootmgr/app/MainActivity.kt b/app/src/main/java/org/andbootmgr/app/MainActivity.kt
index b00fcfde..d8c77aa8 100644
--- a/app/src/main/java/org/andbootmgr/app/MainActivity.kt
+++ b/app/src/main/java/org/andbootmgr/app/MainActivity.kt
@@ -776,9 +776,11 @@ private fun PartTool(vm: MainActivityState) {
 						Button(onClick = {
 							processing = true
 							delete = false
+							val wasMounted = vm.logic!!.mounted
 							vm.logic!!.unmountBootset()
 							vm.logic!!.delete(p).submit {
 								vm.logic!!.mountBootset(vm.deviceInfo!!)
+								if (wasMounted != vm.logic!!.mounted) vm.activity!!.finish()
 								processing = false
 								editPartID = null
 								parts = SDUtils.generateMeta(vm.deviceInfo!!)
diff --git a/app/src/main/java/org/andbootmgr/app/UpdateDroidBootFlow.kt b/app/src/main/java/org/andbootmgr/app/UpdateDroidBootFlow.kt
index e1b42d59..47620e1b 100644
--- a/app/src/main/java/org/andbootmgr/app/UpdateDroidBootFlow.kt
+++ b/app/src/main/java/org/andbootmgr/app/UpdateDroidBootFlow.kt
@@ -77,6 +77,7 @@ private fun Flash(vm: WizardActivityState) {
 				"BOOTED=${vm.deviceInfo.isBooted(vm.logic)} SETUP=false " +
 						"${tmpFile.absolutePath} real"
 			).to(terminal).exec()
+			tmpFile.delete()
 		}
 		terminal.add(vm.activity.getString(R.string.term_success))
 		vm.activity.runOnUiThread {
diff --git a/app/src/main/java/org/andbootmgr/app/ext.kt b/app/src/main/java/org/andbootmgr/app/ext.kt
index 354e0318..e85ecc17 100644
--- a/app/src/main/java/org/andbootmgr/app/ext.kt
+++ b/app/src/main/java/org/andbootmgr/app/ext.kt
@@ -19,7 +19,7 @@ class ActionAbortedCleanlyError(e: Exception?) : ActionAbortedError(e)
 
 @Throws(IOException::class)
 private fun generateFile(prefix: String, suffix: String, dir: File?): File {
-	var n = Math.random().toLong()
+	var n = (Math.random() * Long.MAX_VALUE).toLong()
 	n = if (n == Long.MIN_VALUE) {
 		0 // corner case
 	} else {
@@ -44,7 +44,7 @@ fun createTempFileSu(
 	var f: File
 	do {
 		f = generateFile(prefix, suffix ?: ".tmp", tmpdir)
-	} while (!f.exists())
+	} while (f.exists())
 	val ff = SuFile.open(f.toURI())
 
 	if (!ff.createNewFile()) throw IOException("Unable to create temporary file")
diff --git a/app/src/main/java/org/andbootmgr/app/util/Toolkit.kt b/app/src/main/java/org/andbootmgr/app/util/Toolkit.kt
index b150d505..8c3b2402 100644
--- a/app/src/main/java/org/andbootmgr/app/util/Toolkit.kt
+++ b/app/src/main/java/org/andbootmgr/app/util/Toolkit.kt
@@ -14,9 +14,7 @@ class Toolkit(private val ctx: Context) {
 	private val targetPath = File(ctx.filesDir.parentFile, "assets")
 
 	fun copyAssets(uinf: Runnable, callback: Consumer<Boolean>) {
-		if (!targetPath.exists()) fail = fail or !targetPath.mkdir()
-		if (!File(ctx.filesDir.parentFile, "files").exists()) fail = fail or !File(ctx.filesDir.parentFile, "files").mkdir()
-		if (!File(ctx.filesDir.parentFile, "cache").exists()) fail = fail or !File(ctx.filesDir.parentFile, "cache").mkdir()
+		val shell = Shell.Builder.create().setFlags(FLAG_NON_ROOT_SHELL).setTimeout(30).setContext(ctx).build()
 		var input: InputStream
 		var b: ByteArray
 		try {
@@ -40,12 +38,15 @@ class Toolkit(private val ctx: Context) {
 		val s2 = String(b).trim()
 		if (s != s2) {
 			uinf.run()
+			shell.newJob().add("rm -rf " + targetPath.absolutePath).exec()
+			if (!targetPath.exists()) fail = fail or !targetPath.mkdir()
+			if (!File(ctx.filesDir.parentFile, "files").exists()) fail = fail or !File(ctx.filesDir.parentFile, "files").mkdir()
+			if (!File(ctx.filesDir.parentFile, "cache").exists()) fail = fail or !File(ctx.filesDir.parentFile, "cache").mkdir()
 			copyAssets("Toolkit", "Toolkit")
 			copyAssets("Scripts", "Scripts")
 			copyAssets("cp", "")
 		}
-		Shell.Builder.create().setFlags(FLAG_NON_ROOT_SHELL).setTimeout(30).setContext(ctx).build().newJob()
-			.add("chmod -R +x " + targetPath.absolutePath).exec()
+		shell.newJob().add("chmod -R +x " + targetPath.absolutePath).exec()
 		callback.accept(fail)
 	}