First, let me say that I like this program so far. Even at its current functionality, it's still mostly superior to the one I had been using. So, thank you, Fahim, for writing it.
You're welcome. And thank you for the kind words about the app, the appreciation of the user community always makes the work worthwhile

I would like to have a field in the Submissions dialog for the Return Date of a submission. I would also like for that field to have a column in the Submissions pane.
I thought at first you meant a way to track the various dates involved, such as when you got a response back from the agent, when you sent out a partial etc. I originally planned to capture all those dates but realized that it makes things a bit too cumbersome and so went for the manual approach - track all those dates in the Notes field

quid explained to me that what you meant by a Return Date was simply a way to be warned when you had not heard back from somebody for a certain period of time about a submission. If that is what you meant, will certainly implement it. I was thinking of some sort of alarm feature originally but forgot all about it along the way :p
Contacts:
I would like to see a "Guidelines" section that is separate from the Notes section. Guidelines would be for general information about a contact, Notes would be for my experiences dealing with them.
I have no problem with the feature wish itself - it's the naming that I'd have a problem with since somebody else would come along and say I want to track something else, why don't you add a field for that? :p So how if we call that Custom Information or something and add it in?
I would really like to have a way to mark whether I wish to submit to a contact anymore.
Will add this for the next release - if I forget, bug me :p
Projects:
I would like for both the Synopsis and Notes text areas to be visible when a project is highlighted.
My reasoning for leaving out Synopis was that you would know the synopsis for your story pretty well without having to see it there on the screen. The only reason the Synopsis field is there in the database at all is to be used in the submission template. Of course, I might be wrong in my assumptions and if you can point out where I've gone wrong, I'll be happy to add it

General:
I would like to see the dropdown menus alphabetized.
I will fix this for the next release though some of the results might not quite be what you expected

For instance, the Contact dropdowns usually have different variations depending on what is entered - if you have a Company Name, I believe it's Company Name - First Name + Last Name but if there is no Company Name, then it's just First Name + Last Name. The sorting order will be by whatever is the first letter in the name - not the last name.
For some reason, the first column of each pane (ie, Contact Type in Contacts, Type in Projects, and Title in Submissions) doesn't alphabetize properly. I'll gather some information on this and post it in the Bug topic.
I think I know what you're referring to

This is due to the way things are set up internally ... internally, the Contact Type is a numerical value and when you sort the column, it probably goes by the numerical value instead of the character representation assigned to that numerical value - if that makes any sense :p I didn't think anybody would really bother sorting by the Type column but will check to see if there is a way to fix that ...
The alphabetization algorithm treats lowercase separate from uppercase, so all lowercase titles show up after the uppercase titles.
Will check into this as well.