Section 5.3.1, p82, equation 5.11:
Lander Victor remarks that the definition of the power c in the formula is not clear. In probabilistic calculations c can be considered as a stochast with mean -0.92 and a standard deviation of 0.24.
For deterministic calculations an exceedance frequency of 15% is assumed. The Gaussian distribution gives u_15% = 1,035. So c becomes c=-0.92 + 1.035*0.24 = -0.672.  And 10^-0.672 = 0.21. This is the coefficient in equation 5.10.

Section 5.4, p 99, equation 5.33:
Lander Victor remarks that T_m in eq. 5.33 might be replaced by T_m-1,0, which is in line with figure 5.32, also mentioning T_m-1,0.

Section 6.3.3, p118, equation 6.8
Corrado Altomare remarks that the formula presented here is different from the formula originally presented by Van der Meer, and in the Manual presented as formula 5.24. In that formula a multiplier (1-0.0033β) is used, while in 6.8 a multiplier (1-0.0063β) is used.
Formula 6.8 is restricted to permeable (armourstone) structures under oblique wave attack, while formula 4.25 is for smooth, impermeable slopes.

Neural Network update:
The Neural Network Overtopping tool is freely available now on the Deltares website as a web application. To use this application please visit  https://www.deltares.nl/en/software/630304/overtopping-neural-network and start the application by clicking the following link: Open Overtopping Neural Network on this website.  

Further, in case you still want to use the stand-alone version of Neural Network Overtopping Tool, you can download it from the deltares ftp-account. Below you can find information on this ftp-account.

    Host name = ftp.wldelft.nl
    User name = overtopnn
    Password  = sueu978
    Account   = <leave this blank>
    Directory = <leave this blank>

The URL representation of the account, e.g., for use in a browser, is:

    ftp://overtopnn:sueu978@ftp.wldelft.nl

After downloading, please run the setup. This will install/update the files on your system.

For further inquiries, contact Jan Kramer of Deltares