MR 97 and kiln wash will make your glass stick if applied thick. Remember that any mold that you spray MR 97 with, will no longer accept kiln wash. On the other hand, you can go to MR97 after kiln wash The trick to both these methods is, laying them thinly. Kiln wash works great if you fire the mold first without glass, then fill and fire. Slumping temp is not hot enough to allow the glass to melt and settle in the crevaces of your mold. Up your target temp slightly and hold longer. MR97, gives you a more polished, clean surface, whereas kiln wash is usually matte. If your glass is stuck in a mold, do not force it…..next time youre firing something, simply turn your mold (with the stuck glass) over, set on stilts and full blast. Your glass will melt out and puddle on your kilnshelf, but you will save your expensive mold .I hope this helps..