Hopefully someone here can help me there is not much information out there for this register.

I bought this register thinking I can buy a PAX reader from my merchant. I found out after my purchase that the unit needs to have software from the dealer to use the PAX. The dealer has no clue about this and barely responds to my messages. On top of that I have no idea how to program the unit. I have not even plugged it in yet.

What are my options? Am I better off selling it and taking a loss. Or is it possible to program this myself and actually make use of it. Any help would be appreciated been stressing out over this purchase that is now non refundable.

The TK-1550 is a region specific model that was only available in some areas. I assume you are trying to connect an EFT terminal to it (PAX normally design EFT terminals if I'm on the right track).
Different IPLs (the internal software for the register) are created for different areas of the world and you may or may not need an interface unit between the two devices as well. If you bought this machine from a dealer for connection to EFT, the dealer should have loaded the correct IPL for connection to the EFT that you have in your country. It is not usually cheap to interface to an EFT terminal so be prepared for some extra cost.

The dealer I bought it from screwed me so he will not/cannot program anything.

If I forget about the PAX terminal how do I go about using the register as a standard register. I noticed there is no CC button and want to put my store name on the receipt. Is this easily done?

Look up "programming message" and under that you will see "receipt message". Follow the instructions to set each line of the logo. just the first four lines are for your store name. You will see the example logo on the first three lines. Where you see "entering characters" you just type the new description for that line using the alphabet sheet on the keyboard, then press 00 (double zero) before continuing with the instructions.

To use a credit button, you can just re-name the CHK button to CREDIT.
turn key to program mode. 2 SUBTOTAL. Now type the word CREDIT on the alpha sheet. Press 00 button. Press CHK button. press SUBTOTAL

Thank you for helping me with this.

What about the preset hot keys. Can't they be programmed for the register?

Can pretty much the whole thing be programmed from the register itself without the use of software?

Yes. No need for software unless you needed a special graphic message on the receipt.
The rubber buttons are departments.
Look up department unit price programming and programming department descriptor (use the one called department key). That will allow you to set a name and price if you want to use them as preset item buttons. If you don't program a price, the department will be open which means you type any price each time you use it in REG mode. remember, when typing prices, don't use a decimal point.