(4/5)
There is sufficient documentation for this snippet. Most of it is easily understandable except perhaps for the description, which is worded in a very weird way. Contact information is included, as well as some small information about the parameters that the snippet can take.
 
I would add in the documentation that this snippet only starts working when you join or another person joins a channel, because upon loading this snippet, nothing will work yet.

    (3/5)
This snippet returns the amount of seconds that the specified nick has been on the active channel, or the channel that you specify. Additionally, it also allows you to specify a network.
 
In order to provide this functionality, the author uses an on join event, to add the nickname to a hash table, that has as part of its name the name of the channel, and the name of the network. Because of this, the snippet will not function properly on servers that are not part of a network.
 
I would advise to the author not to use the -c switch with /hinc. This makes mIRC have to increment the hash table value each second, for each hash table entry in each hash table, something that can become quite an intensive task if you have hundreds of nicknames in your hash table. Preferable would be to store a $ctime as value of the hash table item, and to calculate $calc($ctime - $hget(table,$nick)) for the amount of seconds that a nickname has been on the channel/network.
 
There is the option to specify the .dur property, which will make the returned number of seconds formatted with the use of the $duration identifier.
 
Unfortunately, because the author uses an on join event, this identifier will only work on nicknames that have joined after you have. The author should include some aliases that fill the hash tables with all the nicknames upon loading of the addon. It would still not give an accurate measure of how long a nickname has been on a certain channel (because you can't know it), but atleast it would be better than nothing.

Not rated
This is a text based snippet which doesn't require a design rating.

All in all, an identifier that isn't entirely useful, although some might find a use for it. The coding is not bad, has some error checking, but could be improved to leave out some redundant coding. Also be aware that not every server is part of a network, some servers don't have a value for the $network identifier, which will give unrequired results. Finally, it would be a good idea to do some initializing when the snippet is loaded, and to add in your documentation how exactly this snippet works. You shoud do this, because upon loading this snippet, nothing will work, which may cause the user to think the snippet's coding is faulty.