I had the same problem.
Looks like a bug in instalation package.

I did the following:
1) I installed the Wiz.Mounter from the packages present in App.Manager.
This will install it but no icon.
2) Go to following address:
https://garage.maemo.org/frs/?group_...elease_id=2339

and click on wizard-mounter_1.2-maemo4.1_armel.deb

The system will ask if you want to open/download it.
Say open.
Then will ask you if you want to install Wiz Mounter-say yes again.
Will show you the new package is 0 kb.
No problem - go on with instalation.
The system will report success.
And if you check , you'll find the icon and the software works.

I can't explain why, but it does.

Good luck.