I recommend you to pack your EXE with free UPX executable packer.
Your exe will be only 971KB instead of 2.40MB.
If you use compression level -9.
And about Intellisense, it would be better if it automatically displays valid commands at the same time you type code.
Look at Visual C# Express and XNA for example.
At the same time you type code it almost predicts what you want to type. I love this stuff. It makes coding alot faster.
Because you are using SynEdit then there should be alot of example to do that kind of stuff, i even found something like that on the internet, when i was working on my IDE.
Hopefully you can implement this.
OFC: Happy Birthday.