Had a motorcycle. Wrecked it. But! I'm unfamiliar with Ultima's Waterless Wash, but if it's anything like ONR's wash, I think it would be fine. However, I used a leaf blower to make sure to get all the interior parts dry. Along with a MF dry. And I let it sit for a while.
All in all I think you are fine, I was just a little particular for the bike and wanted to make sure it was dry.
2007 E90 335xi - "Sera"
aFe Stage 2 DCI | AE Performance Exhaust | COBB Accessport | HPB Interior LED Kit | M6 Wheels | ER Charge Pipe | MTEC LED Angel Eyes | Helix Intercooler