Well, it's been even more years now... :P
I found an old email exchange with someone who had that error and eventually got it to work, but didn't tell me what was wrong. I suggested:
make sure the dll is registered:
regsvr32 DeviareCOM.dll
and if you are on a 64 bit system:
regsvr32 DeviareCOM64.dll
And got back an answer:
"
1. Start your program
2. Start David 5
I added a messagebox per your instructions and realised that the startorder is important :-)
Voila :)
Thanks for all support!
"
So maybe it was just the start order..