Hi @tcafe,
Hope you are well. I am answering questions from your reference gradually,
#1, yes, you are capable to control the waiting time via user roles
#2, yes, you have an option from Start Download for downloading the file automatically or on the download button click
#3, yes, you can set for downloading the file automatically or on the download button click
#4, yes, you can also use lazy download add-on in the free version
I hope I have answered your above questions. please let me know, how can I more help
Thank you and regards