Version 6.367 installed.
I'm very happy, this is starting to work !!!! 
1- INSTALLATION
After deinstalling and installing the BTT plugin, the BTT profiles are added to my Stream Deck Plus XL, but they are never added to my Stream Deck Plus, my Stream Deck Mobile, or my two Virtual Stream Decks.
I have done this process of deinstalling and reinstalling without success trying different things:
- Unplugging my SD+XL
- Unplugging my SD+
- Changing the names of the devices to change the order of the devices list, putting the "problematic devices" in the first position of the list
2- "SWITCH STREAM DECK PLUGIN PROFILE" ACTION
2.1- TARGET DEVICE
It works perfectly, but there is a cosmetic issue. When I select the devices connected by USB (SD+XL or SD+), the names are substituted by the "All Connected Stream Decks" label. This is the behaviour:
Anyway, the selection is working as expected. When I select SD+XL, the change of profile is only sent to SD+XL. When I select SD+, the change of profile is only sent to SD+.
2.2- PROFILES, PAGES, NAMES (Target Device = SD+XL)
When I set the target device to SD+XL (the only device where the BTT profiles are added) everything is working like a charm:
- I can switch between BTT profiles as expected
- I can add pages succesfully to every BTT Profile (maximum 10 pages per profile)
- I can add/change the config of every button/dial of every page of every BTT profile
- I can edit the name of BTT profiles in SD editor and BTT switches them as expected! *
*The original name of the BTT profile in the BTT action must be not edited for this to work
2.3- PROFILES (Target Device ≠ SD+XL)
When I set the target device to the other devices (where the BTT profiles are not added) and I trigger the "Switch Profile" action, the SD Editor shows a dialog warning that BTT plugin has one or more preconfigured profiles, asking me if I want to install them in the device.
When I accept the installation, profiles are not installed.
Everytime I trigger the action, the dialog is shown as described. Everytime I accept the installation, nothing is installed.
2.4- PROFILES (Target Device = All Connected Stream Decks)
When I set the target device to "All Connected Stream Decks" and I trigger the "Switch Profile" action, the SD Editor shows the same dialog warning that BTT plugin has one or more preconfigured profiles, asking me if I want to install them in THE device.
I wonder if this is correct because I would expect that SD Editor would ask me if I want to install the profiles in ALL devices.
3- QUESTIONS, IDEAS, SUGGESTIONS
3.1- I would consider to only allow values from 1 to 10 in the "Optional Page Number (Base 1)" field. Or leaving it as it is now, but adding an explanation that any value other than 1 to 10 is the same as leaving the field empty.
3.2- I assume that BTT is changing their BTT profiles using identifiers instead of their names. Is this correct?
If this is correct, could BTT change other profiles created with the SD editor if we found out their identifiers?
3.3- I think it would be better to name the BTT profiles with correlative numbers, such as "BTT-01", "BTT-02", ..., "BTT-10", "BTT-11", etc.
This would be practical to make name changes in the stream deck editor and maintain consistency for the user.
For example, I can change the name of "BTT-01" to "01-My Mixer" and put this profile first of all.
Then I can change the name of "BTT-04" to "04-My Selected Track" and put this profile fourth in my list of profiles.
This way, when I'm in BTT configuring the actions, it's easy to know or check that if I have the profile change set to "BTT-01", it means that in the stream deck editor it is the first profile, and that if I have "BTT-04" it is the fourth profile.
3.4- I wonder if it would be possible or very difficult to make it possible for users to define how many profiles they want to add with the installation of the BTT plugin.
This would be very practical for users who want few profiles or for users who want many.
In my case, I have 31 profiles configured on my SD+XL. And I would be interested in all of them being selectable/changeable from BTT.
So, I would be interested in at least having from "BTT-01" to "BTT-31".
But if possible, I would prefer an installation with 50 BTT profiles, from "BTT-01" to "BTT-50" to have empty profiles available if I need to make new profiles.
I can think of two ways this could be implemented:
a1- Have a field in the preferences, next to the plugin installation button, where we could enter a numeric value to define how many profiles we want the plugin to install
a2- Same as before but instead of entering the total amount of profiles, have two fields to enter a range of profiles (for example, install the plugin with profiles BTT-25 to BTT-50). This might be useful to avoid deleting or overwriting profiles BTT-01 to BTT-24, but I don't know if it's necessary or makes sense.
b- Have an installation button like we have now, but with a drop-down menu with various specific amounts of profiles. For example, the drop-down menu could have these options:
- Install the BTT plugin without predefined profiles
- Install the BTT plugin with 20 predefined profiles
- Install the BTT plugin with 50 predefined profiles
- Install the BTT plugin with 100 predefined profiles
- Install the BTT plugin with 200 predefined profiles
I suppose this last option would be the simplest since you would only have to export 5 versions of the same installer with different amounts of profiles, but I'm just speculating. You're the one who knows about that.
PS: Just FYI, I asked the AI if there is a maximum number of profiles and it told me there is not, although it says it is advisable not to have more than 100 profiles to prevent the stream deck from starting up too slowly.