I will answer as the best as I can but, even if I am quite passionate about the generator, I am not an experienced campaign maker.
I created one test campaign for a new map I was working on at the time.... I was blown away by the results. So much so that it influenced my
map making from then on.
Here goes:1) Can I build a campaign with a not moving frontline?
I have seen DGEN mission templates with front lines flags set. I would still think that the front line will move depending on the overall strategic situation.
2) Can I build a campaign with multiple aircraft assigned to the player randomly?
I do not think you can in DGen. You can do it in static campaigns though.
If possible I can cover more long intervals of time in the subcampaigns.
I think you can make it as long as you want, with say 5 missions every day from 1914 to 1918...
2 Can the player use more than an aircraft in the same unit in the same subcampaign?
DGen is geared for sequential aircraft changes (like upgrades... or downgrades). You can keep the same airfield but have operations with different planes.
It is quite an undertaking and I would advise you to go step by step...
- Use a map and planes that are already defined and have a play with ops, campaigns and planes assignations. You may find a way to keep that frontline static.
- After that add the planes you need and their weapons. Have a play... I have only seen campaigns for WWII (maybe because I work with Motor a lot and he only does WWII ...?).
- Then work on adding the map definitions for WestFront. This is not hard but tedious and ask a mapper for help. I reckon you should do this last, you first need answers on your questions about campaign schedules/unfolding of events/plane use.
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One last thing, you have to be prepared to have to try on your own and try, try, try... until you can get it to work. Or find a workaround. Or drop your expectations. This is the only way you will get some outcome and hopefully the one you are after.
The pool of people who can help you is limited (so is their time) and/or English is not their main language.
Having said that it is an awesome piece of kit for those who dare.