Displaying Glyphs

I encounter an issue with displaying glyphs. I have some pro fonts that contain a lot of glyphs (windows fonts like Arial also have some langages in one font file with more than 4000 glyphs). So I tested one with about 1000 glyphs (with a tool that displays it) but in fontbase not half of them are displayed. Has anyone an idea for this? Is it again a problem with the method the font foundries save their fonts? Could this be solved in fontbase? Is’s not that important when the glyphs work in the apps but …