Mission 4 unlocks both missions 5a (nukes) and 5b (battlecruisers). You just have to go back to the campaign selection menu and pick the mission you want. That's what he did at 15:35.
Shox has put a lot of effort into his runs, and he has been streaming most of his attempts. There is no doubt for me about the legitimacy of this run.
Ask for clarification before accusing people of cheating, please.
@CuteDuckk12 It's a new submission of an old run for a new leaderboard.
I had to wait 3 weeks to get a run verified. You can try asking a mod in dms here or in discord to get your run verified or... be patient... 3 days isn't much to wait (don't forget that being a mod isn't a job).
DId your ghosts attacked anything? If i had to guess that would be my bet :)
There is no rule against it, so i would assume that you can.
Usefull resources: Ingame cheats to test things out faster http://classic.battle.net/scc/pcheat.html
Glitches list (there is no unified and complete list as far as i know) https://kb.speeddemosarchive.com/StarCraft/Game_Mechanics_and_Glitches https://www.starcraftai.com/wiki/Tricks,_Glitches_and_Exploits https://liquipedia.net/starcraft/Bugs#Game_Bugs
If you want to play on older versions (not for Remastered): There is surely a better way of doing it but to make it work I installed the game using the original CD, not in the Program Files folder so you can still have Remastered installed and working properly.
Downloadable version changer (not for Remastered) https://www.speedrun.com/tools/SCV.Selector.Full.2011.03.24_a23bn.rar
Patches list https://starcraft.fandom.com/wiki/StarCraft_version_history
For basic game mechanics... go check liquidpedia or some videos on youtube I guess
As MASH said, watching IL and FG runs is a good way to learn.
There is no guide not because there is no special glitches or no refined enough strats... (what are you guys saying lol) there is no guide just because the community is small and noone has put the effort to make one yet.
I will put here what i sent to Nilsi on discord, some resources that might help...
To check maps triggers: ScmDraft 2 (map editor) https://us.forums.blizzard.com/en/starcraft/t/scmdraft-2-alternative-starcraft-map-editor/153
Downloadable Original/Vanilla campaign maps https://www.speedrun.com/tools/Original_Campaign_red1l.rar
Downloadable Brood War campaign maps https://www.speedrun.com/tools/Brood_War_Campaign_8u5vq.rar