post -s"[- zho]" sample_English.cha +1
Here are answers to your questions:
1. You can fix errors in any order you like, as long as in the end CHECK reports no errors found. If you are using ESC-L CHECK, then you will not have a choice of ignoring the first error found, because ESC-L CHECK always starts from the top of the file. It has no continue from current location option.
2. if you use "park@s" instead of "park@s$n", then MLU will give correct result.
The TTR results could be wrong depending on your FREQ command. If you only run FREQ with +s"[- zho]" or
-s"[- zho]" options, then result will be correct with either "park@s" or "park@s$n" choice. If you run FREQ without
+/-s"[- zho]" options, then you will force FREQ to compare words, for example, "park@s" and "park", which are not same, and it will inflate the TTR result. If you use "park@s$n" choice and run FREQ on %mor tier, i.e use "+t%mor -t*" options, then result will be more accurate.
3. Your sample file had "[*tense]" instead of "[* tense]" code, notice missing space character. Maybe that was the cause for failure to find "[* tense]" code. I have added the space character and got correct result searching for "[* tense]" code with this command:
freq +s"[* tense]" sample_English.cha
If you want to count the actual words associated with code "[* tense]", then use this command:
freq +s"<* tense>" sample_English.cha
I hope this helps and Happy New Year!