I tried the demo and there seems to be a lot of visual issues.
Thanks for the feedback. First of all, remember it's an alpha version and it's not its final version. I wouldn't recommend jumping into conclusions without trying it first, that's why I decided to open an alpha testing period for everyone who whises to test it. Keep in mind the demo has more functionality than what construct offers natively, and even more than ProUI, and it's pushing the boundaries of what the engine can do.
First when you click the play button at the bottom, the menus are empty of icons, then the icons appear for a split second outside (as though they have just been loaded in the middle of the frame), then they appear in the menus.
This is not an issue, in the demo I synched the creation of the grid elements after the window finishes animating. But you can instantiate them right away, I'll update it to demonstrate it. Depending of the amount of textures you are loading, you can pre-load them to memory using Load Sprite Sheet to speed up construct's instantiation.
When you click the ui icon on the desktop the same thing happens with the text. Also you can see the text moving as the window resizes itself with easing. By opening and closing them quicky it becomes quite noticeable.
You are right, but that's because I'm mixing html elements with textures-like elements. That's something construct can't handle very well, you will have the exact same results doing it without the addons. That's a construct limitation: Place a text object as child of a sprite, then resize it and you'll see the exact same result.
I think what you have done is great, but i don't think based on this demo it can be used for a professional game in its current form.
Too soon to declare a conclusion tbh. ProUI had these limitations and far more, yet it got used professionally. I'm a ProUI user, I can tell.