The 5S(1/2) -> 5D(5/2) two-photon transition in Rb is of interest for the development of a compact optical atomic clock. Here we present a rigorous calculation of the 778.1-nm ac Stark shift [2.30(4) x 10(-13)(mW/mm(2))(-1)] that is in good agreement with our measured value of 2.5(2) x 10(-13)(mW/mm(2))(-1). We include a calculation of the temperature-dependent blackbody radiation (BBR) shift, and we predict that the clock could be operated either with zero net BBR shift [T = 495.9(27) K] or with zero first-order sensitivity [T = 368.1(14) K]. Also described is the calculation of the dc Stark shift of 5.5(1) x 10(-15)/(V/cm(2)) as well as clock sensitivities to optical alignment variations in both a cat s eye and a flat mirror retroreflector. Finally, we characterize these Stark effects, discussing mitigation techniques necessary to reduce final clock instabilities.