Strictly speaking RocTopple version 1.0 does not perform flexural toppling analysis, only limit equilbrium block toppling analysis as described in Goodman and Bray (1976). Limit equilibrium flexural toppling will be considered for a future version of RocTopple.
However since toppling failure often involves mixed failure modes (e.g. block-flexural), you may be able to analyze a slope with a "flexural" toppling component as long as you are aware of the program limitations and assumptions.
The display of failure modes for individual blocks represents the potential failure mode of the blocks, if the shear strength of the joint planes is reduced by a factor equal to the value of safety factor.
If the safety factor is greater than 1, the overall slope is stable and the block failure mode display represents the potential and not actual failure of the blocks.