Redmine

Hello everyone.
Recently we started using Redmine to manage our projects and it's working great.
Unfortunately, given the environment where we had to install it it was impossible to have it running on a Linux box so we ended up using the Bitnami installer for Windows.

Projects are hosted on a second server with both an svn repository and a shared folder (for all the other miscellaneous files). I've set-up Redmine to access the svn repository and that's working smoothly.
Now, I want to add a second repository (of SCM type - filesystem) to be able to access all those extra files through Redmine and have everything better integrated and referenced. However, I can't seem to get it to access shared folders.

I tried mounting the shared folder as a network drive, for instance to drive letter z: but I keep getting error 500

An error occurred when trying to access the repository: No such file or directory @ dir_initialize - z:/

If I switch drive letter to c: I can access all of my local files with no problem and I can browse and use the shared folder through windows explorer with no issues.

Is it possible to do this? AFAIK the Redmine+Apache server is running under my user so I don't think permissions would be a problem, the shared folder is publicly available anyway... but I'm not entirely sure because, unfortunately, I'm not used to dealing with and managing Windows systems.
So that's why I'm here. Hoping any of you can help me or at least point me in the right direction as to how to solve this problem.

Any help is appreciated.
Thank you all!