Lupus and sudden appearence of rash, should this be a cause for concern?

Yes. This can be part of lupus andma represent a flare of the lupus. Depending on what medications are being taken for lupus a topical press ription steroid should be used to prevent possible scarring.
Not really. Not really. This may be a sign that the symptoms are increasing, and you may need a more aggressive approach to control the lupus.