btw Warboy do you think that you could create sprite creator? e.g. load surfaceset with unit parts and then place them manualy on "animation frames". save all data to file and load it in OpenXcom?
every surface in surfeceset will have 4 values write by this editor for every animation frame:
x,y - position offset
z - draw order
v - visible
Editing could be very "simple":
3 controls [next, prev, list of all] changing frames (probably longest list here)
2 controls [left, right] changing rotation (8 direction)
3 controls [next, prev, list of all] selecting surface group (e.q. chest part, legs, right arm, corpse frame)
4 settings [v,x,y,z] values for current part
1 screen showing unit using with current frame and rotation