Midfunction hooks prolly wont work anymore at all. After one of the last xtrap updates, it scans for wrong bytes at this positions of every d3d function:
1) Bytes 1 - 5
2) Byte 9
3) Byte 13
So you have just 3 bytes for your jump instruction. A short jump or short conditional jump would fit in this space, but xtrap also scans for suspicious opcodes in the functions.
JMP, PUSH..RET, all kind of conditional jumps like JB, JZ ...,