Okay, I was told that SE's customer support sucked, but I didn't realize it was quite this bad:

Agent Paul Y: Hello and thank you for contacting SQUARE ENIX Customer Support. Just a few moments while I review your question, please.
Agent Paul Y: In order for us to more accurately address your issue, we will require additional information. Please give a brief explanation of the issue you are having and please include any error codes or messages you are receiving.
You: I'm trying to switch from crysta to credit card for my payment method
You: However, I have some crysta left on my account
You: I'd like to either get that refunded or use it to partially pay for my next installment
Agent Paul Y: There is no refund and there is no partial payment that can be made on the account
You: Okay, what can I do, then?
Agent Paul Y: You can to continue to use crysta
You: I want to switch to using a credit card
You: I don't want to use crysta
Agent Paul Y: That is your choice.
You: Okay, but you essentially have money on my account in the form of crysta
You: I'd like to get that back or be able to use it without being forced to continue to use crysta to pay for my account
Agent Paul Y: As stated there is no refunds on crysta purchased.
Agent Paul Y: And there is no partial payments that can be made
You: Okay, then what can I do what can I do to use the crysta on my account?
You: Is there anything else I can spend it on other than to pay for my account?
Agent Paul Y: That is up to you. You can either purchase more crysta and use it for another month or you can let it sit it's up to you.
You: If I let it sit, you guys just keep my money without giving me anything for it?
You: That's... kind of shady
Agent Paul Y: I'm sorry you feel that way.
You: Do you have any options for me?
Agent Paul Y: I have already provided the options you have avaliable.
Agent Paul Y: Thank you for visiting the SQUARE ENIX Support Center! Take care and hope to see you online!
Agent Paul Y has disconnected.

I kind of get it about the crysta thing. I mean, you do essentially purchase the crysta and they just don't offer returns. Fair enough. I think that they should have some way to allow you to use it or something, especially since the credit card option wasn't there when we were originally picking payment methods (and I've heard awful things about Click & Buy, so crysta seemed like the lesser of the evils).

I didn't get a chance to register my complaint, though, because the chat agent disconnected me before I could type anything else at all. The speed at which this guy moved to GTFO was amazing. Great support!