Flux-simulator does not accept SIZE_DISTRIBUTION N(300,30)

I am simulating RNA-seq reads using Flux-simulator 1.1. When I provide the option SIZE_DISTRIBUTION N(300,30) the simulation aborts with the following stdout:

[LIBRARY] Nebulization
[LIBRARY] Configuration
Lambda: 600.0
M: 1.0
Max Length: 14588.0
Recursions: 5

Processing Fragments ********** OK (00:00:35)
21061556 mol: in 4999494, new 16062062, out 21061556
avg Len 348.43436, maxLen 4845
initializing Selected Size distribution
[ERROR] 100

However, if I simply remove the above option, it works fine. Could you please explain how this can be sorted.