Here's the create script I've been testing.
It includes asset id, but it has no function. I'm thinking my agent id to asset id idea won't work because once I start adding network devices through the API TRMM won't have agent ids for those. The better workflow would be to use the read API and compare by MAC address when using the update API.
The rest of the script is working on my test PCs. It even includes a desktop/server/laptop check function. I haven't tested it on a server yet, but it does distinguish between laptops and desktops. Most of the script uses Get-WmiObject even though Get-CimInstance is preferred, but I was getting too many errors with CimInstance.
Aside from the requirements, make sure you add the "script arguments" items to TRMM's script arguments section. The script is mostly universal and can be adapted to any RMM. I'll work on a network devices creation script once I figure out PC asset updating with MAC comparisons.
I'm glad I could help.