I had a roll of Bambu Transparent and it appeared fine in the AMS. I ran out of it though and threw out the spool. I just purchased some 3rd party transparent and the option isn’t there for me. So I’m not sure your solution works unfortunately 
Anyone have any other ideas how to add this in manually? I’m on Windows unfortunately
Not sure if this will work with BBS on a Windows box. Try selecting the color icon for the slot in question, go to the RGB slider page, select 256 for all values and move the opacity slider to the far left for a value of 0. This should give you an approximation of transparent.
There is no opacity slider in Windows.
Since you have no ability to enter an Alpha value I see no way to do it with the tools you have available
It is possible that you may be able to use the color picker in the Windows Power Toys to create a custom value and then reference it from the BBS color picker but that is just a guess since I don’t have a windows box to test it on anymore.
I wonder it this is only in newer firmware as I don’t see this behavior on my X1C with 1.6.5.1 firmware. I use BBL transparent all the time but don’t see transparent as an option for third party filaments on my X1C’s filament color menu.
Update: I stand corrected, the color shows up on the color picker in the AMS section, but only if there is currently another spool which is transparent. As soon as I removed the existing transparent spool, the color disappeared from the AMS pick list.
This is my experience also.
Would love them to solve this as its an annoying hassle!
There’s also the dual color or gradient filaments, they show as such in the AMS but it doesn’t seem possible to copy that to a slicer filament profile.
Here’s a data point though: The filament profile’s color is actually a json list so it could theoretically hold several entries. I once tried putting two colors in there (editing the json while slicer wasn’t running), like this:
"default_filament_colour": [
"#123456",
"#789ABC"
],
…but that didn’t work.
I’ve got the same issue, but the strange part is, the “transparent” color was there on initial setup.
I just got my P1S with AMS 2 days ago and when I set it up, I put a transparent spool of generic PLA in slot #1 of my AMS.
(My AMS was: Generic PLA-clear, Bambu PLA-orange, Bambu PLA-green, Generic PLA-white)
When I setup the AMS, it allowed me to choose transparent as the color for my clear filament.
When I would select that filament to print a model, the model would even show up in Bambu Studio with a transparency effect.
After printing a poop box and a tool, I decided I didn’t want my tools to be clear, so I swapped the white and the clear.
Ever since I did that, I’ve been unable to tell it the 4th spool is transparent. That color option doesn’t exist from the selection anymore.
Makes no sense to me.
Seems like this would be an easy fix?