Knytt Stories Level Editor won't open!

It just won't!
The game app starts just fine,and I redownloaded the game,thinking maybe the mfa file was corrupted or something,but it still wont open.

Any ideas?

Are there any error messages when you try to open it?

A clarification: since you mentioned an .mfa file (which is MMF2 source code), are you trying to use the Knytt Stories editor (Level Editor.exe), or are you actually trying to open the Knytt Stories source (Knytt Stories.mfa) with MMF2?

As AA suggests, the way you stated your question leaves many many questions on our side.

Can you be as specific as possible to what you are doing and what is happening?

To give an example:

Patient: Doctor, When I press here, it hurts.
Doctor examins the spot the patient presses but the first scans do not find anything wrong.
Doctor: What kind of pain do you feel? Sharp or blurry pain?
Patient: Sharp pain.
Doctor: I don't see anything. Does it still hurts?
Patient presses that spot and says: yes, it still hurts.

Long story short, it seemed the finger of the patient was broken. Moral: when important information is not presented, people often assume the wrong problem to be the case.

I'm taking a wild guess that you're trying to open the wrong file. The level editor program is called "Level Editor.exe" and its icon is an empty red box. It should be located in the same directory/folder as "Knytt Stories.exe".

Further information: "Level Editor.mfa" is the uncompiled source code. It takes a proprietary software development program called Multimedia Fusion 2 to open it. Unless you want make your own editor, you don't need it. To make your own levels, use "Level Editor.exe".

Very sorry for being unspecific.

I 'm opening the right file,the .exe file with the red square icon. I 've made levels before.
I get no error messages,after the mouse's pointer finishes being in "loading mode" (hourglass) nothing happens.

I have 2 ideas.

1.) Your security software might be blocking it.
Solution: Add stdrt.exe to a safe list within your security software.

2.) It may have closed improperly at some point and is still running as a process.
Solution: Restart your computer, or open your task manager (ctrl+shift+esc) and close stdrt.exe in the processes tab.

Neither was the case.

*don't bother if you don't want to,this is on a laptop and I have a desktop PC back home,which I can't use right now, but I will just continue the level from there*

Have you rebooted your laptop? I have solved the weirdest problems just by rebooting. If that doesn't work, try redownloading the editor. Some files may have become corrupted.