If you click into the comment (click the time just past the name) you can "flag" it, which is the appropriate thing for spam. (Please don't flag comments you merely disagree with, keep it for actual spam or threats, etc).
Under your profile you can also enable "See dead" which will let you see flagged comments.
You can't flag a post if you don't have enough karma. What the threshold is gets tuned periodically, but I seem to remember that you get a lot of features at 500 karma; nanch currently has 409 karma, so I wouldn't be surprised if he can't flag it.
I used his guides when developing for the PineTime and everything worked perfectly. I would have been completely lost without his information.
Thank you Lup!