The objects all allways inserted by XRef in some of the HQPlants libraries. We just take account of this issue, it will be solved in the next patch of the software.
As workaround, you can apply a manual XRef merge after importing, with the "Merge to Scene" in the Xref Object window.
Regarding to the material selection bar, it is disabled because we need to update the HQCatalog package must be updated for Forest 4. Actually the library works in automatic mode, selecting the best fit material for your current selected renderer. This issue will be also fixed soon.