Notes. We adopt a distance of ∼5 kpc to Wd1 (Negueruela et al. 2010); consistent with the Gaia parallaxes for cluster members (Appendix A). Errors on the stellar luminosity and radius assume the cluster distance is well determined and derive from uncertainty in the correction for interstellar reddening (Sect. 4.1.2) and stellar temperature. The error on the spectroscopic mass is derived from the propagation of (assumed) Gaussian uncertainties. We note that R_* corresponds to R(τ_Ross = 2/3). The H/He ratio is given by number and other abundances are relative to solar values from Anders & Grevesse (1989); if we use the values from Asplund et al. (2006) as a reference, the derived ratios need to be scaled by 1.38, 1.537 and 1.86 for C, N and O respectively. Note that f_cl is derived for the inner, line-forming regions of the stellar wind and not for the outer regions responsible for the mm-continuum; see Sect. 4.2 for further details.