If the legs are loose at the crotch joint, then a super small ball of sculpty will fix it. Just put the sculpty on the tip of the "T-Joint" before attaching the top (outer) leg part. Just unscrew the legs like normal and apply the non-dryed sculpty... then put leg back together. please note tho, the sculpty or other material can not be hard. Its needs to form around the joint's tip.

Removing the arms of the modern style is complicated to say the least, and I suggest looking for a youtube tutorial... it will be easier on you.