[Siralos]

Thakyou very much; they are only rotating on Z axis, so, your formulae should do the trick.
Then, to recapitulate; set the main object to Z angle.
Find the X, Y, angle of the relative object and subtract them.
For example: x = 2, y = 2, a=20; then calculate the distance from 0,0 to 2,2... sqrt(2^2 + 2^2) = sqrt( = 2.82
And then the final position will be:
ObjectX[o][0]=floatadd(BasisPosX,2.82*floatsin(Angle,degrees));
ObjectY[o][0]=floatadd(BasisPosY,2.82*floatcos(Angle,degrees));
ObjectA = floatadd(BasisAngle, 20)

Am I right?

Thanks!!!