After some time, I managed to solve this issue. In fact, It was a problem in the hardware and device tree configuration.
I discovered it when probing with another example project named Zybo-hdmi-out (https://github.com/Digilent/Zybo-hdmi-out). However, as this project is for a previous version of Vivado, I tested with Vivado 2017.4. Surprisingly, it worked fine but with another pixel-format in the device tree. The Zybo-base-linux project which I used, has a pixel format in DRM device tree configuration set to "rgb888", however, for the Zybo-hdmi-out, it displayed correctly with pixel-format "xrgb8888". If I use other pixel formats, no output is displayed in both cases.
Going deep into the configuration of both projects, I discovered that there are some differences in the VDMA and Subset converter settings, which changed to the configuration in Zybo-hdmi-out, solves the problem of colors and rendering, considering also a pixel format in the devicetree equal to "xrgb8888". I attached the images of both configurations.
In addition to this, I managed to update the design for the Vivado version I use (2018.2) with no more differences that a change in the AXI memory interconnect replaced by the AXI Smart connect in the newer version, which is added automatically when using Vivado autoconnect tool for the VDMA block.
Hope this information could help others which run in the same issue. Thanks for your help.