First, I'm guessing the photo resolution exceeds your needs (but maybe not). If so, it is definitely worth compressing the images prior to usinf in Visio. Visio files tend to easily get very bloated in my experience.
Next, I assume you were working on this in a location local to your server and not over VPN. I often work on large project files via VPN and this can be very combersome. Not only because transferring files over VPN is generally pretty slow but because D-Tools tends to get agitated when anything takes a long period of time and chokes.
There is a file worth taking a look at. Depending on your OS it may be something like this: C:\Program Files\D-Tools\SI 5\DTools.SystemIntegrator.Navigator.exe.config.
Take a look at the section labelled "FileManagerService" and the CloseTimeout as well as reveiveTimeout values. Depending on circumstances, these values effectively stop a project check-in or check-out if it surpasses the threshold. Sometimes the result is the project says it is checked in but the project files like drawings may be left behind. This results in overwritten files when you attempt to check out the project again. By "adjusting" some values in the above mentioned file I was able to get around this problem. Of course this is all in SI5.5.378.0 not SP2. It is possible that my issue was fixed in SP2 but I am currently planning to wait for SI6 to upgrade
![Fingersx[1]](http://www.d-tools.us/images/smilies/fingersx[1].gif)
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