There is no problem moving Advance Steel projects around your network so long as you maintain the folder structure. Remember every project model (e.g. Project1.dwg) has a folder next to it of the same name (Project1). This folder contains all related documentation in sub folders such as Details, BOM, DSTV etc. You must always move the folder (and all contents) with the model and keep them next to each other. Please check you have this folder and its files in the right place.
Assuming you still have the folder in the same path you should find that the drawings are still linked. If the link is lost you can use the “Register Documents to Model” command in the Document Manager panel on the Output ribbon. This will automatically look in the correct place for the drawings (the Details sub folder). You should select all files in this folder and click Open. Then wait as they are relinked to your model. You should see lots of “Successfully registered” messages on the command line. You cannot link to drawings in any other path. You can use the same command to relink to saved BOMs in the BOMs sub folder and NC & DXF files in the DSTV folder by changing the file type in the open dialog.