Another issue which exist for more versions of AutoCAD:
I have a grid file whereby the gridlines are made with xlines. This file is an xref on all the plan drawings. On most of them i can still snap also when the xref is clipped, but on some not, a bit anoying to me also because i can't find a reason. maybe the distance from the insertionpoint is the reason? the further away the more difficult to find the snap on those xlines?