Maximum Plot Points in Mathcad 15

In my attached Mathcad 15 worksheet, I am trying to compute an IFFT of an analytic function of frequency for a know time function.  To display the desired bandwidth, I have to use a large number of points.  Time points = 2^m and frequency point = 2^(m-1) where m=24.  The final plot will not plot due to the maximum plot points unless the step size is at least 70.  The way I have reduced the plot points means there are only 2 points between the first time point and the next time point at step x Dt.  I tried to do an interpolation from the original vectors to fewer time points; it ran forever.  Maybe user error on the linterp function.  Attached is the xmcd file.  Auto calculation is turned off.  The calculation time on my old PC is about 15 seconds.

1.  Can linterp not interpolate to fewer points?

2.  Is there a better alternative to what I have done?

Thanks much.