Try 'English' as last name and 'R' for first name. After that, select 'Confederate' and nothing else. You should get thirty-nine index references. Two of these are for Richard T. English, one for R. T. English. All three of them are relevant, which I can say after reviewing these files today.
One is from M266, Compiled Service Records of Confederate Soldiers Who Served in Organizations From the State of Georgia, reel 428, 36th (Villepigue's) Infantry Regiment, A--I. War Department clerks often did a poor job of filing papers into the right files. When an officer like Richard English served in more than one command, this is frequently the case.
Records in this file include a receipt signed by English on July 1, 1863, Bayou LaFourche, La. At this time he was assigned to Major's Brigade. Earlier records show that English was Provost Marshal at Port Hudson from Jan. 21, 1863.
The other records are filed under M258, Compiled Service Records of Confederate Soldiers Who Served in
Organizations Raised Directly by the Confederate Government, 1st Confederate Infantry (1st Confederate Regiment, Georgia Volunteers), reel 53, C--E.
Both these files cover the first year of the Natchez Quitman Light Artillery. [English frequently signs as an officer of the N.Q.L.A or Q.L.A.] Are you covering only those records after the battery reorganized for the war? Does your review of the battery include its service at Fort McRee?