1.Yes a descrpancy berween Windows limit of 255 vas LrC statement of 170
2.,As for poping up at 176 vs 170, that probably takes into account additional files/folders to be created
3. Path refers to total path, right down to drive letter, mor folders within folders, the longer the path
4. The lrcat-data file is new to v11, it will have the same name as the catalog, just different extension, .lrcat-data
5. The lrdata folders , the library previews and the smart previews, always have same name as the catalog plus the words Previews or Smart Previews, but having extension .lrdata. LrC needs them to be named that way, if not, LrC will recreate them named that way.