If I may suggest something regarding this simplification idea:
Don't change anything. This will be an awful lot of work and you'll probably break something. Don't get me wrong, I am not doubting your abilities, but Code::Blocks has become sufficiently complex during the last year so this is not entirely impossible.
Instead, add a plugin that catches events such as for example
cbEVT_APP_STARTUP_DONE to display something similar to our "start here" page, but more targeted to someone who has never used an IDE. It could explain what an IDE is about, what you need projects for, and a link "create a project NOW", for example. You could also save the progress in the config for each user, and change that page with time.
You can modify things like the project manager's popup menu or the editor's menu from inside a plugin quite easily (remove or rename some menu items). The same goes for the main menu bar. Settings can be changed, projects and sources be modified.
You might want to look at InfoWindow class and display a few of these at certain key points. Look into
sdk_events.h, there are plenty of events being fired at important milestones, you only need to register to them and you can tell the student what to do now (of course you could also launch a wizard or something else instead).
Why am I suggesting this?
1. It is probably a lot easier (just register to some events and do something in reply), and you don't risk to break anything.
2. When your students are sufficiently advanced (or when they think so), they can simply disable this plugin, and Code::Blocks will immediately work in "pro" mode. No recompilation, no need to download a few megabytes again, no problems installing different versions
The plugin might even be configurable to give up different things independently of each other, for example, you could turn off "simplified project menu" but still keep "beginner's start page".
3. This would be a very cool plugin for us to have too
If you'd consent with this, we could distribute it with the regular version of Code::Blocks, lowering the complete beginner's entry barrier, but not annoying the advanced user at the same time.