Review
https://knowledge.broadcom.com/external/article/150348/installing-winpe10-adk-for-use-in-deploy.html and confirm INSTALLED=False is set for both [WINPE10_X86] and [WINPE10_X64] in the prebootos.ini file (or the version of WinPE you are attempting to import).
This is not an issue with driver manager. WinPE import is performed by bootwiz.exe. If an hourglass is shown, either bootwiz.exe is running, or WinPE import task exists. If it fails - it will be activated by daily schedule or you can force it by selecting any preboot image rebuild (if there is a preboot image/config available).
If you want to execute it manually, you can try to run the following command substituting the version of preboot OS you are using:
bootwiz.exe -install -q -os WinPE10 -x86
bootwiz.exe -install -q -os WinPE10 -x64
You can try to invoke it by task and check NS and bootwiz logs.
Note:
There is a BootWiz.log (e.g. at "C:\Program Files\Altiris\Deployment\Logs\Bootwiz.log") containing command lines that BootWiz was called with like these:
"C:\Program Files\Altiris\Deployment\BDC\bootwiz\bootwiz.exe" -install -q -os WinPE10 -x86 "C:\Program Files (x86)\Windows Kits\10"
Also, if BootWiz cannot import WinPE (ADK), then some error message should be logged there.