Are you sure you're using the right server context when calling the BuildMaster Powershell Asset? If you print out the server name in your asset using $env:computername
do you get back the expected server? If I create a simple plan
##AH:UseTextMode
for server $MyServer
{
PSCall GLOBAL::Test_Powershell_Asset;
}
Where my powershell asset is defined as this one-liner
Invoke-Expression C:\Path\To\PowerShell\script.ps1
Then I am able to run this script, no problem.