My current definitions of the rays and their blockages

[Bring4th_Austin]

how is it possible for blockage (which I associate with impaired functioning), to lead to the physical health and vitality which many negative entities exhibit?

I think that disease is more indicative of lack of utilized catalyst.

Catalyst is offered to the entity. If it is not used by the mind complex it will then filter through to the body complex and manifest as some form of physical distortion. The more efficient the use of catalyst, the less physical distortion to be found.

Blockage in a positive entity, whose key to utilizing catalyst is acceptance, is indicative of unused catalyst, and so blockage can basically be equated with inefficient catalyst use, which manifests to the body as disease.

Blockage in a negative entity does not necessarily indicate unused catalyst as proper use of catalyst would result in the blockage Ra refers to in a negative entity. The blockage is present even when catalyst is properly utilized, or controlled.

49.6 is relevant:

Ra: The entity polarizing positively perceives the anger. This entity, if using this catalyst mentally, blesses and loves this anger in itself. It then intensifies this anger consciously in mind alone until the folly of this red-ray energy is perceived not as folly in itself but as energy subject to spiritual entropy due to the randomness of energy being used.

Positive orientation then provides the will and faith to continue this mentally intense experience of letting the anger be understood, accepted, and integrated with the mind/body/spirit complex. The other-self which is the object of anger is thus transformed into an object of acceptance, understanding, and accommodation, all being reintegrated using the great energy which anger began.

The negatively oriented mind/body/spirit complex will use this anger in a similarly conscious fashion, refusing to accept the undirected or random energy of anger and instead, through will and faith, funneling this energy into a practical means of venting the negative aspect of this emotion so as to obtain control over other-self, or otherwise control the situation causing anger.

Control is the key to negatively polarized use of catalyst. Acceptance is the key to positively polarized use of catalyst. Between these polarities lies the potential for this random and undirected energy creating a bodily complex analog of what you call the cancerous growth of tissue.