function construction - How to input a dynamically changing parameter in NDSolve?

I am trying to solve a system of DEs with additional conditions, and one condition depends on a parameter. Let us consider the following example:

eq = D[y,x]==2;

cond = y[1]==param;
NDSolve[{eq,cond},y[x],x]

How do I make a function that takes the input of a number param and outputs the NDSolve result with the corresponding parameter? I tried to make the condition itself a function, but this doesn't work:

eq = D[y,x]==2;
cond[param_] := y[1]==param
fun[param1_] := NDSolve[{eq,cond[param1]},y[x],x]

PS. There is a somewhat similar question, but there the parameter is of Boolean nature.

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plotting - Plot 4D data with color as 4th dimension

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I have several sigmoidal fits to 3 different datasets, with mean fit predictions plus the 95% confidence limits (not symmetrical around the mean) and the actual data. I would now like to show these different 2D plots projected in 3D as in but then using proper perspective. In the link here they give some solutions to combine the plots using isometric perspective, but I would like to use proper 3 point perspective. Any thoughts? Also any way to show the mean points per time point for each series plus or minus the standard error on the mean would be cool too, either using points+vertical bars, or using spheres plus tubes. Below are some test data and the fit function I am using. Note that I am working on a logit(proportion) scale and that the final vertical scale is Log10(percentage). (* some test data *) data = Table[Null, {i, 4}]; data[[1]] = {{1, -5.8}, {2, -5.4}, {3, -0.8}, {4, -0.2}, {5, 4.6}, {1, -6.4}, {2, -5.6}, {3, -0.7}, {4, 0.04}, {5, 1.0}, {1, -6.8}, {2, -4.7}, {3, -1....

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