Sine table has been split to just a fourth of its degrees (from 0 to 90°) but keeping the same amount of memory space (3600 values, but 14400 effective due to the four sectors split).
The same goes for the atan table, whose values went from 450 to 1800. With this changes the motor can now rotote again as slow as 0.1.Hz, but not yet as with the sinf, cosf and atanf. Increasing table size would fix the problem, but it is not likely right now for the amount of space that is required for collecting data.