Interesting board - it's non standard and I can't get the 'firmware' code to load in keyboard-layout-editor.com so it's hard to imagine what the layout is. Having a + key without a number pad is a new one... Generally speaking your matrix looks good and you've avoided pin D6 which does funny things, so definitely don't start again!
I have noticed a problem though - all the switches in the column with ARROW RIGHT have the diodes soldered in the wrong place. You'll need to move the diodes closer to the switch and add extension wires or this will cause problems. Same thing on the wide key on the left at the top of the bottom picture - the wire needs to connect after the diode (please check the rest of the board as well)
The next thing to check is the pins for the rows and columns - in the config ESCAPE is row 0 column 0 so it has to work if nothing else does. It doesn't, which suggests the pins are wrong... Don't forget you're looking at the back of the board so column 0 is on the right, just to confuse everything!
Let me know if any of that didn't make sense