Errors when compiling your patch:
sp-flowdiv.cpp: In member function `void SPFlowdiv::CollectFlow(flow_src*)': sp-flowdiv.cpp:589: error: invalid conversion from `const char*' to `gchar*' sp-flowdiv.cpp:608: error: invalid conversion from `const char*' to `gchar*' sp-flowdiv.cpp: In member function `void SPFlowtspan::CollectFlow(flow_src*)': sp-flowdiv.cpp:663: error: invalid conversion from `const char*' to `gchar*' sp-flowdiv.cpp:682: error: invalid conversion from `const char*' to `gchar*' sp-flowdiv.cpp: In member function `void SPFlowpara::CollectFlow(flow_src*)': sp-flowdiv.cpp:735: error: invalid conversion from `const char*' to `gchar*' sp-flowdiv.cpp:754: error: invalid conversion from `const char*' to `gchar*'
(fixed these by declaring kern_val as const char*, 3 times)
libnrtype/FlowUtils.cpp:89: error: return-statement with no value, in function declared with a non-void return type
(fixed by changing it to return 0)
After that it compiled. I will now try to test it. If you have any sample flowtext svgs, could you please forward?