Forget TTHome. As long as you've downloaded all/any maps/zones (that have metas) to your PC you can always copy/paste them to your device subject to space.
Instal one new map zone (that has a meta code, activate it with F/A (which will add a new yourmap.meta.dct to the map folder) then just cut/paste the map folder back to your pc & repeat etc. That way each zoned map folder is already activated & ready to copy to the device. Another method is to add a copy of your ttgo.bif and latest F/A straight into each new map folder then run F/A from there.
One of the 9510's (9.510+swap for One & XL) is around 56mb but there are many different versions here [Only registered and activated users can see links. ]