Interestingly... I have Armory and Bitcoin Core v0.25.1 working ok, but the Testnet version of Armory is exhibiting a similar behaviour to what the OP has. Armory Testnet is getting stuck at "Scanning Transaction History".

It is always at 88% (tried it 3 times now)... very strange. I can't find any obvious errors anywhere that are causing this issue. :-/