I was having trouble with the Intptr.zero errors, and I just thought I'd suggest a few workarounds for making them work.
First step is to make sure you have the latest version. Somehow when I started using the trainer, I derped and had an older version.
Second step is to make sure that admin access is enabled. If you click the axe icon in the upper left next to "KongHack", a dropdown menu will appear where you can select "Run as Admin". A restart will be necessary, and on the next run, if you have UAC enabled, you may need to grant the admin access.
If neither of these works, and you're running a mozilla-based browser (i.e. Firefox or Chrome), type about:memory into a new tab.
    Find "Unity Player" in the list. If you're like me and have a gazillion tabs open, Ctrl-F will open a little box you can use to search the     page.
    In the first column in Unity Player's row, you will find the Process ID (PID) this is the important thing, write it down or memorize it.
    Go back to KongHack, click the big button that says select process, then scroll down until you find the matching PID, then select it.
(If you're playing a flash game, the same process applies, just search for the flash player instead of unity)
 
Your hacks should now work.
 

I was aware of the existence of this topic, but I found a problem that was generated by an issue on my end (thus not fixable by a mod). I fixed it with those steps, so I thought I'd post that information.