What you can do under "compose questionnaire" is to sort the questions into different orders or leave differnt questions out. But one question will always be the same one question, in whatever questionnaire you use it.
If the questionnaire differ in some systematic element (a few words, for example), placeholders are a great tool.
> Would it be possible to raise the upload limit for a second project, too?
The 1 MB limit is valid for everyone.
Any as long as you are not using the proteced storage, you can also access images from one project A in another project B:
<img src="../projectA/image01.png">