Hi! I had been facing the same issue, before I did the following:
0. I installed Internet Explorer's 8 dependencies (i.e. .NET 2.0, 4.0, MSXML 3.0, etc.)
1. I opened crossover
2. I went to / opened the bottle, where my Office 365 is installed
3. Clicked "Run Command..."
4. Typed: regedit
5. and...