@skywalger - the object mesh in blender do not support skewing matrices (I think because it is non revertible operation). I would try to avoid scaling group - if objects inside are rotated. This way you avoid skewing. Or - you can rotate objects, but only 90 degress. Also you can rotate group member any angle, around z-axis if you then scale group only in Z-axis.
About naming - lod meshes - have you tried BatchOps ? I is good addon for managing many objects - it has also option for mass renaming of objects inside groups, selected objects etc.
Let me know if this works.