Complex LineTypes

I am trying to import a complex LineType that we were using in AutoCAD. I keep getting the message "Unable to find the requested file: CHAIN.SHX."The documentation about the "Shape descriptor syntax" says that if no path is defined for the shape filename, the library path is searched for the file. Where is the library path?I have also tried loading the CHAIN.SHX file. I get the message "File 'CHAIN.SHX' failed to load." This despite the fact that this file loads correctly in AutoCAD 2005. Any suggestions? We are looking at BricsCAD as a possible plateform to reduce costs, but these and other apparent bugs are driving me crazy (may have to stick with AutoCAD).Please advise.