As this answer explains, "divrei sofrim" refers to a category of halachos instituted by rabbis, but understood as having a Divine imprimatur because prophets were involved in their legislation. They are interesting to me because they are seen by some as having a halachic level between d'orayta and derabbanan laws.
Does this category include all the (great many) laws established by the Anshei Keneses haGedolah?
What does it actually mean that these laws are "between" d'orayta and derabbanan? How are they treated in matters which distinguish between the two statuses, such as
-safek d'rabbanan kulo/safek d'oraisa l'chumro
-ability of (other) rabbinical law as well as Torah law to limit these laws
-yotzeius/shlichus and degrees of obligation
- Are these laws mostly treated as a group with regards to the above, or are there many differences among individual laws?