When I try to insert the background file (.dxf), it either takes a very long time to load or it took so long that I had to use Task Manager to end the program. Is there a solution and explanation for this?
There is both a solution and an explanation for what you are experiencing. The easiest solution is to open the dxf file in ArcMap, Microstation, or AutoCAD and just export out the polylines portion or export out all the layers, except the annotations, separately. If you do this you shouldn't have a problem loading the background layers as separate files.The explanation of the problem is likely the file you have is very large and more complex than it looks. When it comes to complex files it's important to understand that the file size is not the true indicator of how much memory it takes to load it. The program needs to load it uncompressed, into a contiguous block of memory, so, the resolution of the image is really the true indicator of the memory it takes up.
Note that the CONNECT Edition release introduces some improvements with regard to memory management of background layers, which may help.
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