On the contrary, there are some things that you can fix.
I started fixing it a few minutes ago, but I lost what I had so I'll just say what I think could be changed to make this a better script.
In my opinion, I don't like setting too many variables for a small alias. This also leads to the conversion of inches to centimeters. That can be easily fixed without variables in the end, when all calculations have been done.
But, here are some minor things that you can do:
msg $active...
can also be written as
say...
var %inch = $round($calc(0.005 * $uptime),5)
var %record = $round($calc(0.0005 * %record2),5)
can also be rewritten as
var %inch $round($calc(0.005 * $uptime),5), %record $round($calc(0.0005 * %record2),5)
You misspelled 'inches'. :F