New members can only give out grey reputation, it's been like that since rep was introduced. If a new member gives you grey rep then posts enough to become a full member the rep doesn't change from grey to greenThat is not true I have current gray marks from people who have over 400 posts.
When the helpful post feature is used you get 1/4 of the rep you would normally give using the rep icon, so if your rep power is less than 4 you won't give any points with the helpful post feature. Time registered here plays a big part in how much rep you give out, not just how much rep you have yourselfI think the helpfuls stack up and you get a point per 3 or something..