Quote Originally Posted by ander7724 View Post
compare this to the official version, the map size is different almost by half.
official map - 1.29GB
venus map - 753MB

why so much difference?
Two subfiles QSIINDEX.QSI (for Quick Spelling Input) and ISM.IDX (maybe for Intersection lookup) are removed from the official map, hence the smaller size. These two subfiles only work on official retail products sold in China. So it makes no sense to keep them in the Venus map which will be installed on non-Garmin-China devices by most people.

If you really need these two subfiles, you can use gmaptool to extract them from the official map then join them to the Venus map.