For 2nd question, maybeTask.WaitAll is OK, but please notice that you should make sure the two tasks WON'T effect each other, they WON'T have common-shared data...ect, because they are running in parallel.
I'm NOT VERY SURE whether you are running with something like Producing-Consuming, if yes, maybe you have to use something like TDL (Task Data Library).
Reproduce your quesions with ScreenToGif is your choice.
For IIS: IIS Forum,
For WebSite of .NET: ASP.NET Forum,
For others: StackExchange.
For spam-sender or forum urgent issues, Send your Email at: forumsfeedback@microsoft.com