Howdy, these are some screenshots from the demo for an upcoming game of mine called Rogue Planet: Lines of Dead Sand on the GameGuru engine, and another separate engine for the F2P multiplayer counterpart, which will come out after the full game's initial launch, possibly on Itch.io and/or (when I have a solid set in stone date to meet their requirements) Epic Games Store.

Also, this demo is ready to ship, I'm just having a bit of trouble with the standalone executable putting the player in an entirely different level that I didn't make at all. If anyone could help, I'd gladly appreciate it, as all of its levels are present, but inaccessible due to this issue.

The sooner this gets resolved, the sooner everyone can play this 6 level long demo (including nightmare bonus campaign, level transitions, and working cutscenes) on the GameGuru engine.

You can learn more about it at: https://roguesunrivaled.weebly.com/

Ok firstly I had to remove the Storyzone and also what looked like a rogue triggerzone.
Then i replaced the start marker and i was able to run it and create a standalone which loaded on the first level.

However there is a problem ... You said you used " The big Escape " and " Morning Mountain Stroll " as base maps..
I assumed they were the pics you showed that are ok as those are unrecognisable .. However there not the base maps you modified ..

Using stock maps as base maps must look totally different ..You have used the stock maps on later levels and they are almost identical. You cannot use them like that .. They are very distinctive maps and stand out ... You really need to scrap those and make your own ..

I would highly recommend making some maps from scratch, instead of using the ones from the GG editor, provided. To add more uniqueness to your game.

A general observation would be that this has a bit of a "clicked together" look. Here is a little tutorial by DK about having that terrain look less 1997 ish : LINK

A second observation is that scaling fire decals and entities like this while loosing so much texture defintion is not a good idea.

I'm pointing this out because you mention actually releasing this on game publishers and nothing you show here is even remotely near the required quality to even get mixed reviews.

Also, if you could use the edit button and add a bit of information about your game, we'd greatly appreciate it. Otherwise I'd have to move this to bug-reports.