Hi there,
I find the most effective thing to shrink lipomas is a move from a processed diet to a real food low starch diet. It will probably also help inflammation subside and make the back end more comfortable.
The lipomas and weight gains suggest Dampness is an issue, particularly given the diet. An inappropriate diet can tax the Kidneys, both in Chinese and biomedical terms, so a move away from a processed diet may be all that is needed to support them. Otherwise, the combination of Dampness, low back issues, weight gains and Kidney deficiency puts me in mind of Yi Yi Ren Tang (Coix Combination). Although not particularly possessing any Kidney tonics, we do notice that a lot of dogs who benefit come across as Kidney deficient. They also often sit with their legs stuck straight out in front of them, like you're seeing. Particularly if the diet is changed, I would expect it to make the dog feel a lot better.
Another option is San Ren Tang (Three Seeds Combination). Like YYRT, it also has a dispersing effect on Wind Damp pathogens invading the Tai Yang at the low back, which is suggested by the evident Dampness and the deep pulse occurring in association with low back pain.
As to your last question, I give all salient symptoms equal weight when assessing a case, although naturally it is critical to cover the ones that are more severe. I measure acute vs. chronic on a hemodynamic basis, with deep pulses in a dog with low back inflammation implying a chronic problem in which we need to drive blood to the area to actively resolve the inflammation. If the dog had the same mild severity of signs, but the pulse was slippery, I would assess the inflammation in the low back as acute despite that mildness, and would want to use a formula that has an 'ice pack' effect on the low back, such as Si Miao San.
Hopefully that makes sense and was what you were asking