I'm having trouble placing anything in the grids - I've got quite a few of the answers, but I've hit a wall, in that there's 2 12-letter answers, both of which I've solved, but which appear to not have a space in the grids that they fit into. One of them (QUERCUS RUBRA) splits into two words of 7 letters and 5 respectively, but the other one (TELEPRINTERS) doesn't break in any way that make two viable words - do I just split it into workable gaps anyway? Seems a bit unsatisfying.
Can you at least clarify for me: is there a themed answer for every letter of the alphabet? That would help me to assign some more to a grid, if that's the case.
I think I'm almost there: I've placed everything; all I can't get is in the top half of the second grid: LO?E?/M???E?T?, I??A?S?A? and SA?????, which I can probably get with the crossing letter from the other two.