Why was the Feat in FSL stuck after setting large EVs ?

I have one question about  FSL

When I use the full model setup in the Feat_higher level analysis, my model has 40 inputs and 20 EVs. After I clicked the "done", the design matrix did not emerge. Furthermore, GLM and Feat seemed to be stuck and any click cannot receive response.

However, if the number of inputs and EVs were setup smaller, like 10 inputs and 5 EVs, it would not encounter this problem.


Version Info.

Ubuntu: 14.04, amd 64

FSL: 5.0.8