I cant figure out where to input my encryption key to view my form results.

That's it. 

Hi,

As per checking your form, in the Preference > Advanced tab, you have the Encrypt Form Data settings disabled.

 

For you to be able to decrypt you form data, the settings shown above should be enabled. If you still have your existing key, you may use it to decrypt your form data.

Regards.

I've changed it to that since submitting, because I can't get the form to
decrypt.
The key entry only pops up some of the time (None of the time in Chrome),
and then it won't submit my key, it only allows me to find it in folders,
but won't complete the upload.
...

Even so, because I've toggled the setting, I still have past entries that
I'm unable to view. How can I resolve that?
...

Like my colleague already mentioned you will need to set Encrypt Form Data to Yes inside of form preferences. Only then you will be able to decrypt your previously submitted encrypted data. I have checked your form and encryption is still set to No. Once yous set Encrypt Form Data to Yes select I will use my existing key option. 

After that open yous submission page and upload your key. I saw that you have posted another question about your key. Please see an answer my colleague provide you on that thread: 

https://www.jotform.com/answers/1024097 

Also please read this guide to find more about Encrypted forms: 

https://www.jotform.com/help/344-Encrypted-Forms-and-How-to-Use-Them 

Hope this will help. Let us know if you need further assistance.