I gave it a try and must say that it didn't quite click with me.
First of all, I like the general idea of the game. Walking through it I could kind of guess what you where trying to accomplish here, however the game is not really there yet. On the plus side, the hypnotic background music really works. Everything else does not.
Quote: "It is very minimalistic"
Thats the main issue with the game. I can tell that you tried to create a lonely, sterile scifi atmosphere with it but you also entirely relied on stock props. While there are indeed some scifi props that gel well with the greyish modern aesthetic you also have a whole bunch of props that are just extremely awkward. Things like a rustic couch with warm, a worn water cooler or cheap looking colorful bookcases are incredibly jarring to see in this environment. GG has limited render capabilities, you can not drown out these inconsistencies with color correction, other forms of post processing or dynamic shadows.
The fact that you use as few props as possible makes all these wildly different assets in tone and style stick out immediately. The best example are these gigantic biohazard warning labels on the glass in places where they have no place being. The solarium/winter garden area being the best example. You can easily airbrush these out of the texture with any art software. (this is a bare minimum kind of thing) You can use the free software paint.net to convert the .dds files if your art tool doesn't support that format.
* Given that this is a very static environment, you can try lightmapping
: It would mean that the furniture casts shadows and doesn't look so floaty but most of all, it would help decrease the effect of the unfortunate lighting you currently have. Some rooms are just a black void with brightly lit random props sticking out. See attached screenshots for examples. I think this is the second biggest visual weakness of the game, it kills the atmosphere.
* The doors have a very slow opening animation, making you try to walk through what looks like an opening for a couple seconds you can not until the collision switches off when the animation finishes. Players outside the GG community will ridicule this immediately as they are not aware and less forgiving of GG stock prop quirks.
* The gameplay mostly consists of walking and reading. Thats totally fine but I personally don't think having to walk through these long, featureless corridors only to end up in a place with almost zero interactivity is particularly engaging. Slow burn puzzle games need pacing too
* To fix the issue with some props lighting up as glaring white while others don't when you use the flashlight, open the .fpe file of these models and add or replace the effect line with this: "effectbank\reloaded\entity_basic.fx" . You can edit .fpe files with notepad.
* You can retexture props without modeling kowledge. Given that this thing has very few entities, you can probably do it all of them in roughly 30 minutes. Give the random stock props a more metallic, futuristic sheen or so.
* The tropical island thingie was quite alright but had this "default game guru" vibe. Apart from some obvious LOD stage pop in. You can also adjust that in the .fpe file.
Just my impression and a few suggestions. Maybe some of it is useful to you.