mset9: get more people to remove it

- Reword uninstalling mset9 to removing mset9 for consistency and so that people hopefully don't skip it
- Add an additional message right before the finalizing setup link to make even fewer people skip it, hopefully
- Move Assert id0 troubleshooting to the top of mset9 (it's the first error people are likely to encounter)
- Add MSET9 detected to troubleshooting
- Update to script v1.5.0, which adds proper(ish) MSET9 detection

_pages/en_US/installing-boot9strap-(mset9).txt

@@ -103,7 +103,7 @@ These instructions must be followed **EXACTLY**, so double-check EVERYTHING you
 {% include_relative include/install-boot9strap-safeb9sinstaller.txt %}
 {%- include_relative include/configure-luma3ds.txt %}
 
-#### Section IV - Uninstalling MSET9
+#### Section IV - Removing MSET9
 
 In this section, you will remove MSET9 to prevent further issues. (This will not remove the custom firmware that you just installed.)
 
@@ -119,5 +119,8 @@ Do NOT skip this section! If you do, applications may crash unexpectedly and you
 {% include_relative include/luma3ds-installed-note.txt %}
 ___
 
+Did you follow Section IV (Removing MSET9)? That section is MANDATORY!
+{: .notice--danger}
+
 ### Continue to [Finalizing Setup](finalizing-setup)
 {: .notice--primary}

_pages/en_US/troubleshooting.txt

@@ -438,6 +438,30 @@ This likely indicates that you already have custom firmware. You should [check f
 
 ## Installing boot9strap (MSET9)
 
+{% capture compat %}
+<summary><u>assert(id0_count == 1) AssertionError</u></summary>
+
+You have multiple ID0 folders. To determine the correct folder, follow these instructions:
+
+1. Rename the `Nintendo 3DS` folder to `BACKUP_Nintendo 3DS`
+1. Reinsert your SD card into your console
+1. Power on your console
+1. Wait for the console to generate the SD card data
+    + Your applications will have disappeared. This is normal and will be resolved shortly
+1. Power off your console
+1. Insert your SD card into your computer
+1. Navigate to the `Nintendo 3DS` folder on your SD card
+1. Write down the first few characters of the folder you see
+    + This is your true ID0, which we will keep in the real Nintendo 3DS folder
+1. Delete the ID0 from the current `Nintendo 3DS` folder
+1. Move the true ID0 folder from the `BACKUP_Nintendo 3DS` folder to the `Nintendo 3DS` folder
+1. If it exists, move the `Private` folder from the `BACKUP_Nintendo 3DS` folder to the `Nintendo 3DS` folder
+
+Once you've done this, continue from [Section I Step 7](installing-boot9strap-(mset9)#section-i---prep-work).
+
+{% endcapture %}
+<details>{{ compat | markdownify }}</details>
+
 {% capture compat %}
 <summary><u>(title/import).db does not exist, create them now?" / invalid database</u></summary>
 
@@ -495,30 +519,6 @@ Alternatively, your SD card may be improperly formatted or partitioned. Try refo
 {% endcapture %}
 <details>{{ compat | markdownify }}</details>
 
-{% capture compat %}
-<summary><u>assert(id0_count == 1) AssertionError</u></summary>
-
-You have multiple ID0 folders. To determine the correct folder, follow these instructions:
-
-1. Rename the `Nintendo 3DS` folder to `BACKUP_Nintendo 3DS`
-1. Reinsert your SD card into your console
-1. Power on your console
-1. Wait for the console to generate the SD card data
-    + Your applications will have disappeared. This is normal and will be resolved shortly
-1. Power off your console
-1. Insert your SD card into your computer
-1. Navigate to the `Nintendo 3DS` folder on your SD card
-1. Write down the first few characters of the folder you see
-    + This is your true ID0, which we will keep in the real Nintendo 3DS folder
-1. Delete the ID0 from the current `Nintendo 3DS` folder
-1. Move the true ID0 folder from the `BACKUP_Nintendo 3DS` folder to the `Nintendo 3DS` folder
-1. If it exists, move the `Private` folder from the `BACKUP_Nintendo 3DS` folder to the `Nintendo 3DS` folder
-
-Once you've done this, continue from [Section I Step 7](installing-boot9strap-(mset9)#section-i---prep-work).
-
-{% endcapture %}
-<details>{{ compat | markdownify }}</details>
-
 {% capture compat %}
 <summary><u>assert(mii_ok==1) AssertionError</u></summary>
 
@@ -733,6 +733,14 @@ The script has detected that the Nintendo 3DS folder is missing AND that you hav
 {% endcapture %}
 <details>{{ compat | markdownify }}</details>
 
+{% capture compat %}
+<summary><u>Error #18: MSET9 detected</u></summary>
+
+You didn't remove MSET9 when prompted to. Follow [Section IV - Removing MSET9](installing-boot9strap-(mset9)#section-iv---removing-mset9), then re-run the script.
+
+{% endcapture %}
+<details>{{ compat | markdownify }}</details>
+
 ---
 
 ## Boot issues on consoles with custom firmware