Hello Michael,
I wouldn't have thought that access there is a sensitive issue ... but if anyone thinks so, pls educate me ...
Scrub on the range can be pretty dense, depends a bit on where exactly you go ... sorry, but my memory is too patchy, can't help with specifics.
1 day to Rim Lake should be possible, for myself I'd allow 2.
Map sketch below, road marked in bright blue is easy walking, the last few kms are a well formed track. Route shown in bright green is also possible, I'd prefer that one coz I prefer to be off forestry style gravel roads. You need to be reasonably confident as an off-track navigator though.
Not sure what you mean by "small road about 5-6kms south from Derwent Bridge" ... wrong direction?

- access to Travelers Rest Lake
- map Traveller Rest Lake access.jpg (74.19 KiB) Viewed 5170 times