You’re missing one connection – the left side of R2 (5.6k) and R4 (10k trim) should to be connected to the negative 3340 supply (the wire that goes to pin 3, i.e. to the right side of R3 (620 ohm)).
Also, R9 (470 ohm) should probably be in series with a 10 nF capacitor (similar to R7), but it looks like all LMNC designs have it directly to GND and so does my own “LMNC-inspired” builds 
so that doesn’t seem to cause any problems.
Some random suggestions:
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Use a 0.2 or 0.3 inch footprint for the timing capacitor C2, so you can fit a polyester if you have one (putting a narrow component in a slightly wider footprint is easier than the other way around).
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Consider adding 100 nF decoupling ceramics to the power pins on both ICs (from +12 V and −12 V to ground, close to the ICs). They’re not in the stripboard layout, and you don’t need to populate them if you don’t have any, but since you’re doing a PCB anyway…
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Did you just pick random 16-pin and 8-pin chips/sockets? That’s fine (if possibly a bit confusing) if you’re just aiming to create a working layout, but if you want to make the schematic nicer, you can find the real things in the library (at least there’s a ton of TL072s in there). Make sure to double-check the footprints if you’re doing this, though.
I posted some more tips here earlier.