Ampersands in button labels don't create an accelerator (e.g. &Go does not underline the G).
In true VB6 you could plop down a Label control and just start typing to change it's contents. Here you have to focus on the input field first (and you can't just click the "Caption" heading, you have to click within the input column). To maintain fidelity, one of the rows in the Properties grid should always be highlighted when a control is selected on the GUI designer (for Labels this defaulted to Caption, and I believe for controls without a specified default it defaulted to Name).
When switching to a different control with a property matching the name of the currently selected one, VB6 would maintain the selection on that property. This made it quick and easy to update for example the Tag property a bunch of controls in sequence with minimal clicks.
Obviously the menus for Debugging, Save, Help, Add-ins, etc. are missing implementation.
A working Build button that spits out an "exectuable" that runs in the browser would be killer!
My nitpicks are born out of love ;-).