3D FlipBook - Getting so many errors in console

Hi I am planning to buy full version of jquery plugin but before that I tried to implement flipbook using demo version in our application. It works fine but have few issues:

1. Its working fine in most of the cases but in some cases pdf does not load and I see blank
2. I see lots of Exceptions in console from your js library.(see below)

three.min.js:formatted:1302 Uncaught TypeError: Failed to execute 'shaderSource' on 'WebGLRenderingContext': parameter 1 is not of type 'WebGLShader'.
    at ee (three.min.js:formatted:1302)
    at new af (three.min.js:formatted:1448)
    at cf.acquireProgram (three.min.js:formatted:1632)
    at v (three.min.js:formatted:2771)
    at od.renderBufferDirect (three.min.js:formatted:3359)
    at r (three.min.js:formatted:2724)
    at od.render (three.min.js:formatted:3612)
    at VisualWorld.render (3dflipbook.min.js:9)
    at VisualWorld.animate (3dflipbook.min.js:9)

Could you please assist in that so that I can make sure we are good to buy full version.