Due to the release order of the series and its effect on things like water masking there is a correct install sequence and a wrong install sequence which can cause 'water' problems.
To install the England and Wales Volume 1-3 no specific order is required as they were produced and released at the same time.
The Volumes for Scotland were produced in a specific sequence and it should be followed to avoid any problems. The sequence is Volume 4, 5, 6, 8 and lastly 7.
If you have installed then out of sequence simply use the ordering slider in the scenery library to move them about, up or down your listing.
If you have purchased Earth Simulations Isle of Man scenery you must ensure that the terrain folder for that scenery is below the terrain folder entry for Volume 8. Failure to do so will flatten a good part of the Mull of Galloway
Volume 9 and 10 Ireland excluding Northern Ireland do not affect the other volumes.
