The lizard was in every scene featuring the Imperious Leader. Glen Larson rejected the first design of the Imperious Leader because he thought it was too scary for the audience. The second design was simply awful and ugly, but there was no time any more to change it. So the character was shown only from behind or from the distance in a dark room (which in turn was a good choice because it didn't allow the audience to get a full view at the Leader's look so that it had to use its imagination to fill in the gaps). Unfortunately the lizard became so small then that it remained almost completely unnoticed (even I didn't know that it was there before I saw the close-up galleries on byyourcommand.net). However, due to the latest BluRay release the lizard has (finally) become visible again!
There are quite a few eps of the old series and a series of splendid compilations of the new series on Youtube. It has to be noted that there is the old series (called TOS) which we all love and there is a sequel called "Galactica: 1980" which we all ... well, let's say, would love ... to put under lock and key till world ends

..! (The only good things of G1980 are the flying Turbobikes, scenes featuring the Cylons, all new space scenes done by Universal Hartland, the Buck Rogers blasters in "Space Croppers", and the last episode with Starbuck repairing the Cylon.)
Check out these fan edits to see what G1980 could have been:
BTW, two other reasons for watching the new show are: RON D. MOORE & GARY HUTZEL. Should sound familiar (both made DS9 so good

!) .
One of the reason for watching the old show: ANDREW PROBERT (he designed: the Cylon costume, the Viper helmet, a large variety of fleet ships, the TMP Enterprise, the Enterprise D, the Romulan Warbird ...

)!