My friends, I got the answer for you, it's quite simple.
The reason CrossOver is not opening the right application is because the files are associated with CrossOver.app rather than the windows app itself. Now, when you try to open a file with CrossOver.app, CrossOver attempts to open that file with whatever association it has in the Windows Registry from the Default Bottle.
SOLUTION:
1) In the CrossOver menu, go to
2) Programs > Run Command...
3) type "regedit" and press Enter. The Registry Editor will open.
4) In the HKEY_CLASSES_ROOT you got all the files associations. Go to the file association you are trying to fix. Ej: [HKEY_CLASSES_ROOT\.txt]
5) In the (Default) key there's a value, in this example the value is "txtfile" (do not modify this value).
6) Now that you know what the value is, go to "HKEY_CLASSES_ROOT" + the value you saw in the (Default) key + "shell\open\command". In this example it would be [HKEY_CLASSES_ROOT\txtfile\shell\open\command]
7) Modify the (Default) value in this route with the path for the .exe file you wish to use and add %1 at the end. In my case i wanted to make Notpad++ the default app to open txt files so this key became "C:\Program Files\Notepad++\notepad++.exe %1"
(If you have any doubts where the exe file for you application is, go to Configure > Manage Bottles, select your bottle, go to Advanced > Open C: Drive in finder)
I hope this helps.
Regards,
JCD