Decoding your horrible writing is hard, but:
1- It is up to you if it has incest or not. If you do apply the patch, it does. If you don't, it doesn't.
2- If it is good?? Let's do a small exercise, how many posts in this thread? #41.764 Do you think this many posts about a bad game? Another, 340 reviews, giving it a 3,70 average. Maybe this could tell you enough. Even more, the original post has 2,453 reactions. The thread has 22 Million views. Being good or bad is subjective, one man's treasure is another man's trash. So, instead I went for OBJECTIVE and FACTUAL numbers.
3- The size. Indeed. It is enormous. They even call him Zeus.

Oh... wait... you meant the game... Yes, yes, yes... it's over 25Gb right now. With decent but not overly dimensioned graphics and no animations and no music. It is indeed Gigantic. Hours, upon hours of content. By my estimations, at a normal speed and NO FUCKING SKIP, considering 10 to 12 hours play per day, it will take more than a week to go from start to where it is now. Now, the fun part, there's 86 updates so far, each update has at least one sex scene, most have 2, several have more. I guess the average may be around 1,8 scenes per update. This means more porn than you can Fap to without setting your pee-pee on fire. It is an absurd amount of content.
4- The several parts. They are a way to manage the download size. But, they are also a way for the Dev to make upgrades to his code, to the UI, to whatever he wants, without needing to worry about retro compatibilities. Each part is a separate entity connected only by a save made at a VERY specific point in each part. The parts are therefore NOT compatible. Can NOT be merged. Exist for OUR convenience and allow the Dev some code stability.
For a more detailed way to deal with the parts, there's an How-To in my signature.
Another small tidbit. No one here really cares if you will play it or not. If you'll like it or not. What your interests are or aren't. I answered because I was bored, this was a distraction from doing a rather boring chore.
Please do try to write better, it denotes some respect for who's going to read you.
Peace