[mkgmap-dev] mkgmap and MapInstall (OS X)

Every several month I render my own europe from geofabrik extract, with OSX 10.11.6 and a style-sheet based on openfietsmap. Mkgmap output is then converted to .gmap with JaVaWa MapConverter and viewed in BaseCamp. This time, with mkgmap_3972 and splitter_583, the resulting map seems to be ok in BaseCamp, but MapInstall rejects to send anything to the device - no tile of the map is selectable. I reproduced this failure with a fresh europe-latest a second time, while a smaller extract (Nordrhein-Westfalen) works. Downgrading to last used mkgmap_3820 solved the problem in MapInstall - the rendered europe-output is functional for the whole workflow. Is this a bug or something new in mkgmap I have to adjust in my style? Thanks for reading!