Woo! That's a lot to do. I was ignoring some of the challenges which were just rewards for grinding. Argh.
Thanks...
Next question: I seem to read that there is a way to cheat the challenges by adjusting something called "chel" but I don't know what file that is in or how to do it...
You're going to need this (see attached file).
Extract to game folder, run the .bat file, enable console and developer mode.
In game, load your save. Now you can press Shift+D to open the developer mode and check out the game's variables.
there is no real guide here, and the names can be confusing. but some are straight forward to understand (gold, eng, strength, str_exp, etc). You can change their values when you open the console (Shift+O) and write things like "gold = 5000". and poof, you're swimming in money.
Now, each challenge has a corresponding variable (some have more), the main variable for each challenge is chel<#>, where <#> is the number of the challenge. For example, challenge 25 would be chel25.
If you set a variable like that to 1 or 2 (most seem to need 2), the game would consider that challenge completed.
Now, there is also a variable called chel_all. you need to increase it by 1 for each challenge you modify.
When this number reaches 26 (maybe it will also work if you just edit it to 26), it will trigger the completion of the last challenge (completing all challenges). when that is triggered, you will get to see the sequence of the secret ending, then choose when to trigger the actual ending in the garden.
I hope that helped.