Multilayering does not select newest init time

[Marilyth]

Recently singlelayering was changed to always choose the latest init time possible per default, this change is not reflected in multilayering but should be.

Also it may be beneficial to carry over the singlelayering selection over to the multilayering.
E.g.

1. Layer A has Level 250 selected
2. Layer A is chosen as a Multilayer
3. Multilayering has level 250 selected

As opposed to

1. Layer A has Level 250 selected
2. Layer A is chosen as a Multilayer
3. Multilayering has the first possible Level selected