Crash every time on multiple computers + update to new version

Megaglest 3.7.1-3 crashes on Ubuntu 14.04 every time after few minutes of playing. Happens on multiple computers. Upstream reported that they are not interested in investigating the crash since there is already version 3.9.1 released. So to fix the crash I suggest that latest upstream version is taken into use.

If someone is interested in fixing the crash to 3.7.1, I won't probably be providing any more information as I'm going to install the latest version via unofficial way as a work-a-round for the problem. But here is the stacktrace which I was able to get:

#0 0x00007ffff49abf79 in __GI_raise (sig=sig@entry=6) at ../nptl/sysdeps/unix/sysv/linux/raise.c:56
#1 0x00007ffff49af388 in __GI_abort () at abort.c:89
#2 0x00007ffff49a4e36 in __assert_fail_base (fmt=0x7ffff4af6718 "%s%s%s:%u: %s%sAssertion `%s' failed.\n%n",
    assertion=assertion@entry=0xa51e52 "rendering == false",
    file=file@entry=0xa51df8 "/build/buildd/megaglest-3.7.1/source/shared_lib/sources/graphics/gl/model_renderer_gl.cpp", line=line@entry=39,
    function=function@entry=0xa51f80 "virtual void Shared::Graphics::Gl::ModelRendererGl::begin(bool, bool, bool, Shared::Graphics::MeshCallback*)") at assert.c:92
#3 0x00007ffff49a4ee2 in __GI___assert_fail (assertion=0xa51e52 "rendering == false",
    file=0xa51df8 "/build/buildd/megaglest-3.7.1/source/shared_lib/sources/graphics/gl/model_renderer_gl.cpp", line=39,
    function=0xa51f80 "virtual void Shared::Graphics::Gl::ModelRendererGl::begin(bool, bool, bool, Shared::Graphics::MeshCallback*)")
    at assert.c:101
#4 0x00000000009f72b5 in Shared::Graphics::Gl::ModelRendererGl::begin(bool, bool, bool, Shared::Graphics::MeshCallback*) ()
#5 0x00000000005efd9d in Glest::Game::Renderer::renderUnitsFast(bool, bool) ()
#6 0x00000000005f0639 in Glest::Game::Renderer::renderShadowsToTexture(int) ()
#7 0x0000000000526306 in Glest::Game::Game::render3d() ()
#8 0x000000000053ba47 in Glest::Game::Game::renderWorker() ()
#9 0x000000000053cc40 in Glest::Game::Game::render() ()
#10 0x000000000062480b in Glest::Game::Program::loopWorker() ()
#11 0x000000000065c242 in Glest::Game::glestMain(int, char**) ()
#12 0x000000000065f578 in Glest::Game::glestMainWrapper(int, char**) ()
#13 0x00007ffff4996ec5 in __libc_start_main (main=0x4bd3d0 <main>, argc=1, argv=0x7fffffffdfb8, init=<optimized out>, fini=<optimized out>,
    rtld_fini=<optimized out>, stack_end=0x7fffffffdfa8) at libc-start.c:287
#14 0x00000000004c33f8 in _start ()