My 38cc made by the same company, just with a different colour scheme and brand-name also has the carb vent window, the only way I've been able to change it around was when I took the top cover off, that's when you can take it off and turn it around. I couldn't find any info about it on the manual, but it's functionality is very clear.
I assume you could pop it out if you remove the air filter cover and push it out with a screwdriver, assuming you've got access on yours (it seems the plastic finish on these isn't quite equal on each saw... So they're unique, art?)
As for oil leaks, they have an oil filter right at the oil pickup line by the tank, underneath... and this is where they often leak, also there's no vacuum release valve for the oil tank but there is an open hose for it, I had to zip-tie it into place so it wouldn't fall out and start leaking during horizontal cuts.
The way the oil pickup and filter fit into place makes it very prone to leaks, in fact with the vibrations the cup popped out on mine and it took an angry oily piss all over the place.
Nothing some silicone and heat-shrink tubing couldn't fix though, it just meant having to take it all apart.
Here's a pic of the silicone after being applied, I levelled it out afterwards. Not the prettiest, but it hasn't leaked ever since (aside from a few drops from the bar, which is common)
Mine came with a worn out worm drive from the oiler and the aforementioned vacuum line from the oil tank was popped off and capped with a screw (?) -- Didn't take much to bring it back to life. Came with a real Walbro carb also!
For the money, can't complain at all... in fact it keeps impressing me. It has however crapped out a few times after heavy-ish use -- wouldn't start again until cold... loss of compression due to the expansion I guess? the rings don't seem stuck though...
