See: http://helpx.adobe.com/flash/kb/problems-using-flash-authoring-across.html

Issue

When using Adobe Flash across a local area network (LAN) and networked drives/folders, you may experience any of the following problems:"

• Flash crashes while performing a test movie on FLA files located on a networked drive or folder.
• FLA files get corrupted when opening from or saving to networked drives or folder.
• Flash does not reflect changes in custom class after compiling.
• Flash, Flash Video Encoder, or Adobe Media Encodercrashes or corrupts Flash Video (FLV) files while encoding source located on networked drives or folder.
• Flash Video Encoder or Adobe Media Encoder crashes or corrupts FLV files where the output folder is a networked drive or folder.
• Published Flash Player (SWF) files and projectors are unable to load content located on networked drives or folder.
• More than one instance of a SWF or Projector on client machines cannot play back FLV files located on a networked drive or folder.

Reason

The Adobe Flash IDE, FLV Encoder, Adobe Media Encoderand Flash Player were not designed to function across LANs.

Solution

Use of Flash files across local networks is not supported in any context. Published content should access data through a web server. All file sources should be opened and saved on the local system. Using Flash in such a scenario for project collaboration or content deployment is highly discouraged and may corrupt your source files.

If you need to work in a collaborative environment or store source files on a server, use the project panel and/or a third-party version control system.

SERIOUSLY? I cannot work on files located on a mapped network drive? How did they mess that one up? Does the Flash IDE really open the source file and wipe it clean to do the saving, rather than saving a copy first then replacing it as an atomic file system operation? How hard would it be for them make a dummy temporary file for saving then issue a MOVE command?

Any workarounds for this, like something that can make a network drive as stable as a local drive, like some kind of automatic local caching and synching?