Hi,
I have experience for 15+ years in electronics/embedded development.
I have several years of advanced AVR/arduino development, including library development from scratch. Practically all Arduino AVR boards used, like: 2009, 2010, UNO, MEGA, NANO, MICRO, MINI, etc. Several shields used like Ethernet (W5100, ENC28J60, etc.) with various IP protocols implementation, various graphical TFTs with and without touchscreen and various BUS types (parallel, SPI, I2C, etc.), all kinds of sensors and buses, serial and parallel memories, etc.
You can send me your sketch, make a resume on what and how is the hardware connected (or schematic), what the sketch is supposed to be doing and where seems to be the problem and I'll give my best to find your bug.
If you are interested in my bid, feel free to contact me.
Regards,
Carlos.