Ok damn it, i'm out of ideas without being there. Frustrating to the extreme, for you especially. Points opening & closing i guess. get a 6 volt dc battery plug coil & run total loss, or charge the battery from the yellow lighting coil wire which is sort of what happens anyway. Actually i had an AG100 running off the lowest lighting coil wire experimenting when dealing with a crook source coil. Not helping am i sorry.

Also, i see a wayward chain had wiped the end off the cover of the selector drum retainer. Important to replace that although its still semi retained in your case. Usually wipes the complete end off the drum then it lets the drum move sideways & can try to engage two gears at once which aint good..

Source coil resistance on a CT3 says 2.1ohms so i guess its similar for CT1except CT3 went to a lighter flywheel so maybe a different stator but no too far different in resistances i'd think.

I can see the wires associated with the points are isolated from the chassis... scratch that thought.... 
Almost thinking to unplug stator from the harness and put a jumper to see if it will spark then... If it does.. then the wiring loom has a short.. hide and go seek?
Sneezles61

Motor mount bolts 'tight' as has to earth to the frame to get the top coil going. Unlikely i know.

Seems like maybe you should go back and make some measurements to isolate where the problem is located. You mentioned being electrically challenged, but making measurements is a better way than replacing stuff. If you have a quality multimeter, or can borrow one, you can drill down and find the source of the problem. I would start by disconnecting the lead from the magneto assembly to the wire harness/coil so the mag is isolated from everything else. Set your meter to 300-400VDC at the 1MS update time. Kick the bike over and you should see 200-300 volts peak. (only lasts for 2-3MS). If you have that, your problem is either in the wire harness or ignition coil. If not, the problem is in the magneto. If in the magneto, you need to test each component. Switch your meter to ohms and check the system resistance between the mag output wire and ground (earth to the UK/NZ boys). When the points are open, you should see approx. 2 ohms. When closed, zero ohms. If not, one of the components is bad. If you get the 2/0, but don't get 200-300 volts, you probably have a bad source coli or very weak flywheel magnets. If you don't get the 2/0, you need to test each component. Disconnect the points and measure them directly. Open should should show infinity, closed should show 0 ohms. The condenser (separated from the coil and points) the should show a brief continuity, quickly followed by infinity as it charges up (on the ohms setting). Switch to capacitance setting and you should see 0.1 to 0.3microfarad. The source coil is just a 70-80ft length of copper wire wound around a steel core so should read about 2ohms, but should show infinity between wire and core. One (or more) of the parts will not check out if you don't have spark. Replace whichever fails the tests.
alnarv

Some good troubleshooting methods from others. I had the same problem on my DT175. Everything tested good until I checked the plug cap. Mine has a resistor cap. I removed the cap, and when I tested it, there was no continuity. Got a new one, which tested good at 6Kohms. Now I have spark.

Check your red wire to points carefully.  looks too short.  Should be tucked under the coil.  The way it is the points cam will likely rub through the insulation very quickly if it hasn't already.

Just throwing this out there as a possibility. I can't tell for sure from the pic but it almost looks like the solder at the connection to the condenser might have spilled over onto  the outer shell and thus grounding it.  

Theres a very good suspect there.. correct it and see what happens..
Sneezles61