> .bst, .cls and .sty files are all essentially the same in this regard; they > belong > in a TeX tree.
Then, why do you put a browse button next to the droplist in the bibtex dialog, if all .bst files should be under global or local texmf tree, and be listed in the droplist? My point is that if the browse button is there, it would better either work in all cases (fix the space problem) or give a warning when a .bst file with spaces in its path is chosen, rather than giving the user an output without bibliography silently. Bo