I think it's not necessary to know how it is named:
»Playmobil custom« (100% or less) or »Custom/Model for Playmobil« or other »names«...
You will probably find out, that in some themes (especially the train theme!) you need non-playmobil material to get what you want, cause it's too big: you need too much material (it's very expensive to buy it from DS) or there aren't useful Playmobil parts or there are foreign parts, which are very useful for that, what you want.
For example:
• a very big water tower (~1 m) of buckets and flower pots or
• a roundhouse of plastic crates or
• a turntable of a flower-pot saucer or
• a loco which can't be made only of Playmobil (cause of its shape) or
• a 4 meter ship
• ...
I will put there some playmobil parts (windows, doors, handles, railings, chimneys, part of caravan of the construction theme,...) to get a better connection to my Playmobil. So its design looks like made of Playmobil.
I'm curious to see whether parts of this ship are Playmobil parts (windows, doors, handles, railings,...).
And if they would build in some smoke generators for »real« model smoke.