Hi list, Recently I have encountered with the problem that I cant update UVs and Usernormals clusters on the mesh. Situation is here: I have a some custom op connected to some original geometry ( input ) and setted on the some result geo ( output ). Work is going in the operator update callback. Topology of the result geo is changeable and can has more of polygons than in the original one. It also has a UVs and usernormal clusters ( both created as "always completed" ) which must be resized respectivetly to the topology changes. But problem is that nothing similar to resizing simply doesnt happen, when I have a result topology with a greater number of polys and try to update clusters values with UVCls.Set ( const float * _pValues, LONG nbNodes ) - I get crash. And at this time, GeometryAccessor reports a valid nodes count. Furthermore, if I call UVCls.GetValues ( CFloatArray& ) I will get the size of CFloatArray is valid also. So, I cant understood what I am doing wrong or is it a bug. If topology is not being changed - UVs updates fine. I have also looked at this threads http://www.xsibase.com/forum/index.php?board=14;action=display;threadid=35564 http://www.xsibase.com/forum/index.php?board=14;action=display;threadid=41707 and seems like that my problem is the same. Are there possible workarounds ( even something like CCOMApiHandle ways ) ? Thanks, -Oleg