Punya, as your intentions seems very good I wouldn't worry too much. I'd like to make another observation,though.
I wonder if the people who act as the "dharma police" and intimidate newcomers don't incur more negative karma than someone who from lack of familiarity breaks the etiquette a bit. Just my observation after 17 years in dharma centres- the same stories seem to repeat themselves.
People should also be aware how they explain the rules. If something is done with a whisper and a smile , maybe you keep a newcomer interested in Buddhism. If the correction is done is a disdainful or intimidating way, maybe you turn someone away from the dharma.
First impressions count for a lot.
In order to ensure my mind never comes under the power of the self-cherishing attitude,
I must obtain control over my own mind.
Therefore, amongst all empowerments, the empowerment that gives me control over my mind is the best,
and I have received the most profound empowerment with this teaching.
brtsal ba'i bkhra drin