What's the best way for me to share the project here? Screenshot? I don't see a way to post attachments here.

You'll have to upload the .capx file to a 3rd party storage (for ex. Dropbox, Google Drive) and copy the link here without the https://www part since the forum won't let you post links because your account is new.

It also depends on the level of your programming and algorithmic thinking skills. If you are a beginner in the topic, C2/C3 will be a great tool to teach you algorithmic thinking, but it will take time (just as with any other tool). If you are a seasoned developer, you might want to try your luck with Unity or UE4 as well to see which one fits your needs the most.

I'm importing png images to the background but they get a fine line in the transparent part of the image when I use them as tiled background, has anyone had it?

I don't think I encountered the problem before, but showing a screenshot of the problem might get you help faster.

You might want to put it up to stores where people sell game licenses. For example:

https://www.marketjs.com/

I'd suggest searching through Udemy for online courses or search for "Construct 2 Academy" on YouTube.

ErekT Thank you for posting your results.

— Thank you for detailing this to me. I wish success to your product and I see it as an example of what can be achieved with the engine if the developer optimize the game well.

I know that Construct is kind of marketed towards beginners, but heck, I think it is the absolute best 2D-engine out there, my own game is actually starting to look pretty damn good. And I would never be able to do something like this if it wasn't for construct. (if anyone is interested, have a look at http://pixelshade.se)

I have adapted performance level to suit the Shield TV in 1080p60fps and Shield Tablet in 720p60fps (to simulate Nintendo Switch performance)

Your game looks great <img src="{SMILIES_PATH}/icon_e_smile.gif" alt=":)" title="Smile"> I don't want to start an off topic discussion here, but did you run into any performance issues while you developed your game? What kind of optimization techniques do you use? In the video it looked very smooth.

— I'm not going to use Unity just because the lighting is so weird in it and I can't make nice lighting, while in Construct I can, with ease.

Just do some demo projects before you use lights in your project.

But something still not clear to me it's if C3 is a more powerful engine than C2 and if it reaches more or less GM2 engine. ¿What do you think?

C3 uses the same runtime as C2, only with a new editor that runs in the browser. Scirra stated that they'll rewrite the whole runtime for C3, but that could take years.

1 - Only with 3rd party addons. C3 is a 2D engine and while you can achieve isometric games and such, you'll have to rely on 2D images only without 3D models.

2 - It is able to run games like that, but those games had very serious optimization techniques to keep the game running at a high framerate. You might want to read about that before starting a game like those. If you do start a similar game, make sure to test often on slower devices too (don't leave testing to the final stages of your project).

They still dont have advertising for developers.

Advertisement will start once C3 reaches the stable stage.