if a user gets finally enough ability and the certain amount of merits for the account to be upgraded to a higher level, does the number of smerits increase as well?
No, nothing will change except your rank. from Full Member to Sr. Member
from the merits that this account is rewarded from others what percentage of them are becoming smerits?
0.5 sMerit for every 1 Merit. if you do not send merits, you will have 75 Smerit + Initial distribution merits.
= 75 + ((YearActivity/378) * 0.2 * 100) sMerit.[1]**
If you do not remember your "YearActivity", check this file:
https://docs.google.com/spreadsheets/d/12saLhlUoqIdairxzuSPu6EYGrt7FN2lOstO1yDjCEbA/edit.
** These calculations are only for "rank-up" account (from Full Member to Sr. Member) and have not sent merits.
Source [1]
https://bitcointalk.org/index.php?topic=3342949.msg35131159#msg35131159